Exhibit 99.1

	News Release		Marshall & Ilsley Corporation
			770 North Water Street
			Milwaukee, Wisconsin 53202
			414 765-7700 Main
			414 298-2921 Fax
			mibank.com
	For Release:	Immediately
	Contacts:	Greg Smith, senior vice president, chief financial officer 414 765-7727 Dave Urban, vice president, corporate treasury 414 765-7853

MARSHALL & ILSLEY CORPORATION ANNOUNCES SECOND QUARTER RESULTS

Milwaukee, Wis. – July 17, 2006 – Marshall & Ilsley Corporation (NYSE: MI) today reported 2006 second quarter net income of $203.7 million, or $0.79 per diluted share, as compared to $183.7 million, or $0.79 per diluted share, in the second quarter of 2005. Second quarter net income increased 10.9 percent over the same period in 2005.

Net income for the six months ended June 30, 2006 was $390.5 million, or $1.57 per diluted share, compared to $349.1 million, or $1.50 per diluted share, in the first half of 2005.

Earnings for the quarter and the six months ended June 30, 2005, include a $16.2 million after-tax gain, or $0.07 per diluted share, resulting from the sale of a venture capital investment, net of related expenses.

The results of operations and financial position as at and for the three and six months ended June 30, 2006, include the effect of the previously announced acquisitions of Gold Banc Corporation, Inc., and Trustcorp Financial, Inc., which were both completed on April 1, 2006. As of April 1, 2006, Gold Banc Corporation, Inc., and Trustcorp Financial, Inc., had assets of $4.9 billion. The acquired companies had loans of $3.9 billion and bank issued deposits of $3.1 billion. The combined purchase price for these companies, which included approximately $146 million of cash, was $898 million.

Return on average assets based on net income for the second quarter was 1.53 percent, as compared to 1.73 percent for the same period in 2005. Return on average equity based on net income was 14.36 percent this quarter as compared to 17.52 percent for the second quarter of 2005. Without the gain on the sale of the venture capital investment, net of expenses, the return on average assets for the second quarter of 2005 would have been 1.58 percent, and the return on average equity for the same period would have been 15.97 percent.

The Corporation’s provision for loan and lease losses was $11.1 million in the second quarter of 2006, versus $13.7 million in the same period last year. Net charge-offs for the period were $9.9 million, or 0.10 percent of total average loans and leases outstanding this quarter, and $11.9 million a year ago or 0.15 percent of total average loans and leases. At June 30, 2006, the allowance for loan and lease losses was 1.03 percent of total loans and leases, compared to 1.12 percent a year earlier. Nonperforming loans and leases were 0.49 percent of total loans and leases at June 30, 2006, and 0.41 percent at June 30, 2005.

Assets at June 30, 2006, were $54.4 billion, compared to $43.5 billion at June 30, 2005. Book value per share was $22.81 at June 30, 2006, compared to $18.76 for the same date a year ago. Total loans and leases were $40.4 billion, compared to $32.1 billion at June 30, 2005.

Marshall & Ilsley Corporation (NYSE: MI) is a diversified financial services corporation headquartered in Milwaukee, Wis., with $54 billion in assets. Founded in 1847, M&I Marshall & Ilsley Bank is the largest Wisconsin-based bank with 196 offices throughout the state.  In addition, M&I has 42 locations throughout Arizona; 17 offices in Kansas City and nearby communities; 15 offices on Florida’s west coast; 15 offices in metropolitan Minneapolis/St. Paul, and one in Duluth, Minn.; three offices in Tulsa, Okla.; and one office in Las Vegas, Nev.  M&I’s Southwest Bank subsidiary has 15 offices in the greater St. Louis area.  Metavante Corporation, Marshall & Ilsley Corporation’s wholly owned technology subsidiary, provides virtually all of the technology an organization needs to offer financial services. M&I also provides trust and investment management, equipment leasing, mortgage banking, asset-based lending, financial planning, investments, and insurance services from offices throughout the country and on the Internet (www.mibank.com or www.micorp.com). M&I’s customer-based approach, internal growth, and strategic acquisitions have made M&I a nationally recognized leader in the financial services industry.

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This press release contains forward-looking statements concerning M&I’s future operations and financial results. Such statements are subject to important factors that could cause M&I’s actual results to differ materially from those anticipated by the forward-looking statements. These factors include (i) the factors identified in M&I’s Annual Report on Form 10-K for the year ended December 31, 2005 under the heading  “Forward-Looking Statements” which factors are incorporated herein by reference, and (ii) such other factors as may be described from time to time in M&I’s SEC filings.

Note:

Marshall & Ilsley Corporation will hold a conference call at 11:00 a.m. Central Daylight Time Monday, July 17, regarding second quarter earnings. For those interested in listening, please call 1-800-500-0920 and ask for M&I’s quarterly earnings release conference call. If you are unable to join us at this time, a replay of the call will be available beginning at 2:30 p.m. on July 17 and will run through 5:00 p.m. July 24, by calling 1-888-203-1112 and entering pass code 334 28 00.

Supplemental financial information referenced in the conference call can be found at www.micorp.com, Investor Relations, after 8:00 a.m. on July 17.

Marshall & Ilsley Corporation
Financial Information
(unaudited)
	Three Months Ended						Six Months Ended
	June 30,		June 30,		Percent		June 30,		June 30,		Percent
	2006		2005		Change		2006		2005		Change
PER SHARE DATA
Diluted:
Net  Income	$0.79		$0.79		0.0	%	$1.57		$1.50		4.7	%
Basic:
Net  Income	0.81		0.80		1.3		1.60		1.53		4.6
Dividend Declared	0.270		0.240		12.5		0.510		0.450		13.3
Book Value	22.81		18.76		21.6		22.81		18.76		21.6
Shares  Outstanding (millions):
Average - Diluted	258.3		233.9		10.4		249.4		233.3		6.9
End of Period	254.0		229.7		10.6		254.0		229.7		10.6
INCOME STATEMENT ($millions)
Net Interest Income (FTE)	$381.8		$321.4		18.8	%	$714.3		$628.5		13.7	%
Provision for Loan and Lease Losses	11.1		13.7		-19.0		22.1		21.9		0.9
Data Processing Services	345.0		282.4		22.2		688.0		565.3		21.7
Wealth Management	56.3		48.1		17.0		109.1		95.2		14.6
Service Charge on Deposits	25.0		23.7		5.5		47.5		47.0		1.1
Mortgage Banking	12.3		11.2		9.8		24.7		19.4		27.3
Net Investment Securities Gains (Losses)	1.0		29.4		-96.6		2.1		35.3		-94.1
All Other	44.8		39.5		13.4		85.7		74.6		14.9
Total Non-Interest Revenues	484.4		434.3		11.5		957.1		836.8		14.4
Salaries and Employee Benefits	307.1		269.0		14.2		584.5		514.1		13.7
Occupancy and Equipment	63.8		50.9		25.3		121.6		104.2		16.7
Intangible Amortization	12.0		8.1		48.1		20.9		16.2		29.0
Other	161.4		131.8		22.5		322.4		268.3		20.2
Total Non-Interest Expenses	544.3		459.8		18.4		1,049.4		902.8		16.2
Tax Equivalent Adjustment	7.7		8.5		-9.4		15.6		16.6		-6.0
Pre-Tax Earnings	303.1		273.7		10.7		584.3		524.0		11.5
Income Taxes	99.4		90.0		10.4		193.8		174.9		10.8
Net  Income	$203.7		$183.7		10.9	%	$390.5		$349.1		11.9	%
KEY  RATIOS
Net Interest Margin (FTE) / Avg. Earning     Assets	3.24	%	3.42	%			3.25	%	3.43	%
Interest Spread (FTE)	2.65		2.97				2.67		3.01
Efficiency  Ratio	62.9		60.9				62.9		61.9
Efficiency  Ratio  without  Metavante	51.2		49.9				50.1		50.2
Return on Assets	1.53		1.73				1.57		1.68
Return on Equity	14.36		17.52				14.96		17.07
Equity / Assets (End of Period)	10.58		9.84				10.58		9.84
Marshall & Ilsley Corporation
Financial Information
(unaudited)
	As of
	June 30,		June 30,		Percent
ASSETS ($millions)	2006		2005		Change
Cash & Due  From  Banks	$1,281		$976		31.3	%
Trading Securities	55		22		150.0
Short - Term  Investments	281		283		-0.7
Investment  Securities	7,175		6,241		15.0
Loans and Leases:
Commercial  Loans & Leases	12,219		9,612		27.1
Commercial  Real  Estate	13,859		10,029		38.2
Residential  Real  Estate	8,221		5,877		39.9
Home Equity Loans & Lines	4,537		4,978		-8.9
Personal  Loans and Leases	1,551		1,650		-6.0
Total  Loans and Leases	40,387		32,146		25.6
Reserve for Loan & Leases Losses	(415)		(360)		15.3
Premises and Equipment, net	569		449		26.7
Goodwill and Intangibles	3,155		2,160		46.1
Other  Assets	1,931		1,567		23.2
Total  Assets	$54,419		$43,484		25.1	%
LIABILITIES & SHAREHOLDERS' EQUITY ($millions)
Deposits:
Noninterest Bearing	$5,773		$5,089		13.4	%
Bank Issued Interest Bearing Activity	11,818		9,881		19.6
Bank Issued Time	7,772		4,306		80.5
Total Bank Issued Deposits	25,363		19,276		31.6
Wholesale Deposits	7,595		6,786		11.9
Total  Deposits	32,958		26,062		26.5
Short - Term  Borrowings	6,778		5,162		31.3
Long - Term  Borrowings	7,476		6,471		15.5
Other  Liabilities	1,449		1,510		-4.0
Shareholders'  Equity	5,758		4,279		34.6
Total  Liabilities  &  Shareholders'  Equity	$54,419		$43,484		25.1	%
	Three Months Ended						Six Months Ended
	June 30,		June 30,		Percent		June 30,		June 30,		Percent
	2006		2005		Change		2006		2005		Change
AVERAGE  ASSETS ($millions)
Cash & Due  From  Banks	$1,031		$939		9.8	%	$1,006		$929		8.3	%
Trading Securities	50		26		92.3		42		24		75.0
Short - Term  Investments	374		271		38.0		345		230		50.0
Investment  Securities	7,134		6,162		15.8		6,729		6,132		9.7
Loans and Leases:
Commercial  Loans & Leases	11,897		9,357		27.1		11,119		9,109		22.1
Commercial  Real  Estate	13,580		9,867		37.6		12,089		9,693		24.7
Residential  Real  Estate	7,986		5,368		48.8		7,632		5,050		51.1
Home Equity Loans and Lines	4,595		5,099		-9.9		4,650		5,114		-9.1
Personal  Loans and Leases	1,592		1,603		-0.7		1,669		1,627		2.6
Total  Loans and Leases	39,650		31,294		26.7		37,159		30,593		21.5
Reserve  for  Loan  &  Leases  Losses	(416)		(361)		15.2		(392)		(361)		8.6
Premises and Equipment, net	565		445		27.0		531		448		18.5
Goodwill and Intangibles	3,139		2,154		45.7		2,819		2,148		31.2
Other  Assets	2,061		1,723		19.6		1,951		1,709		14.2
Total  Assets	$53,588		$42,653		25.6	%	$50,190		$41,852		19.9	%
Memo:
Average Earning Assets	$47,208		$37,753				$44,275		$36,979
Average Earning Assets Excluding Investment
Securities Unrealized Gains/Losses	$47,320		$37,741				$44,360		$36,953
AVG  LIABILITIES & SHAREHOLDERS' EQUITY ($millions)
Deposits:
Noninterest Bearing	$5,404		$4,826		12.0	%	$5,174		$4,760		8.7	%
Bank Issued Interest Bearing Activity	11,640		9,850		18.2		11,055		9,863		12.1
Bank Issued Time	7,647		4,194		82.3		6,602		4,028		63.9
Total Bank Issued Deposits	24,691		18,870		30.8		22,831		18,651		22.4
Wholesale Deposits	8,045		6,600		21.9		7,288		6,701		8.8
Total  Deposits	32,736		25,470		28.5		30,119		25,352		18.8
Short - Term  Borrowings	3,419		3,392		0.8		3,395		3,144		8.0
Long - Term  Borrowings	10,050		7,920		26.9		9,729		7,565		28.6
Other  Liabilities	1,692		1,665		1.6		1,682		1,666		1.0
Shareholders'  Equity	5,691		4,206		35.3		5,265		4,125		27.6
Total  Liabilities  &  Shareholders'  Equity	$53,588		$42,653		25.6	%	$50,190		$41,852		19.9	%
Memo:
Average Interest Bearing Liabilities	$40,801		$31,956				$38,069		$31,301
Marshall & Ilsley Corporation
Financial Information
(unaudited)
	Three Months Ended						Six Months Ended
	June 30,		June 30,		Percent		June 30,		June 30,		Percent
	2006		2005		Change		2006		2005		Change
CREDIT  QUALITY (a)
Net Charge-Offs ($millions)	$9.9		$11.9		-16.8	%	$15.9		$19.8		-19.7	%
Net Charge-Offs / Average Loans & Leases	0.10	%	0.15	%			0.09	%	0.13	%
Loan and Lease Loss  Reserve ($millions)	$415.2		$360.1		15.3	%	$415.2		$360.1		15.3	%
Loan and Lease Loss  Reserve / Period-End     Loans & Leases	1.03	%	1.12	%			1.03	%	1.12	%
Non-Performing Loans & Leases (NPL)     ($millions)	$198.0		$131.6		50.5	%	$198.0		$131.6		50.5	%
NPL's / Period-End Loans & Leases	0.49	%	0.41	%			0.49	%	0.41	%
Loan and Lease Loss Reserve / Non-     Performing Loans & Leases	210	%	274	%			210	%	274	%
MARGIN  ANALYSIS (b)
Loans and Leases:
Commercial  Loans & Leases	7.26	%	5.84	%			7.09	%	5.69	%
Commercial  Real  Estate	7.34		6.15				7.17		6.03
Residential  Real  Estate	7.01		5.97				6.94		5.88
Home Equity Loans and Lines	7.21		6.23				7.09		6.08
Personal  Loans and Leases	7.20		5.91				6.97		5.75
Total  Loans and Leases	7.23		6.03				7.08		5.90
Investment  Securities	5.19		5.03				5.18		5.02
Short - Term  Investments	4.94		3.16				4.61		2.98
Interest Income (FTE) / Avg. Interest Earning     Assets	6.90	%	5.84	%			6.77	%	5.73	%
Interest Bearing Deposits:
Bank Issued Interest Bearing Activity	3.26	%	1.70	%			3.09	%	1.54	%
Bank Issued Time	4.24		3.02				4.10		2.89
Total Bank Issued Deposits	3.65		2.10				3.47		1.93
Wholesale Deposits	4.79		3.00				4.60		2.80
Total Interest Bearing Deposits	3.99		2.39				3.80		2.22
Short - Term  Borrowings	5.06		3.36				4.90		3.23
Long - Term  Borrowings	4.68		3.91				4.59		3.88
Interest Expense / Avg. Interest Bearing     Liabilities	4.25	%	2.87	%			4.10	%	2.72	%
Net Interest Margin(FTE) / Avg. Earning     Assets	3.24	%	3.42	%			3.25	%	3.43	%
Interest Spread (FTE)	2.65	%	2.97	%			2.67	%	3.01	%
Notes:   (a)   Includes Loans past due 90 days or more.
(b)   Based on average balances excluding fair value adjustments for available for sale securities.