Rule 424(b)(3)
File No. 33-38033

NALCO CHEMICAL COMPANY

COMMON STOCK ACQUIRED UNDER THE
NALCO CHEMICAL COMPANY
1990 STOCK OPTION PLAN

APPENDIX DATED MAY 10, 1995
TO PROSPECTUS DATED NOVEMBER 30, 1990


This Appendix updates certain information in the Prospectus dated November 30, 
1990 (the "Prospectus") relating to shares of Common Stock which may be offered
by the stockholders listed herein under the caption "Selling Stockholders" or
by their transferees (or by their donees or pledgees).  The Company will 
furnish without charge to participants additional copies of the Prospectus 
upon request.

SELLING STOCKHOLDERS

The following table sets forth the name and position within the Company for 
the last three years of each Selling Stockholder, the number of shares of 
Common Stock of the Company beneficially owned by him on the date of this 
Prospectus and, the number of shares offered by the Prospectus.

                                                              Shares Offered
                                                              by This
Name and Position                     Shares Owned (1)(2)     Prospectus (2)
W. E. Buchholz                                   34,700        33,700
Vice President-Chief
Financial Officer

P. Dabringhausen                                 55,739         53,900
Group Vice President,
President, Process Chemicals 
Division

M. B. Harp                                      121,418(3)       86,500
Executive Vice President,
International Operations from 
January, 1993 to December, 1994; 
and Executive Vice President,
Operations as of January, 1995

E. J. Mooney President and Chief Operating       323,467         231,000
Officer from January, 1992 to March 
1994; President as of March, 1990; 
Chief Executive Officer as of April, 
1994; and Chairman as of July, 
1994.                           

S. D. Newlin                                       57,113          48,200
General Manager, Pulp & Paper 
Chemicals Group from January, 
1992 to December, 1992; Vice 
President, President, Nalco Pacific 
from January, 1993 through 
February, 1994; Group Vice 
President, President, Nalco Europe
as of March, 1994.

J. D. Tinsley                                       77,308          59,700
Group Vice President, President,
Water & Waste Treatment Division

W. S. Weeber                                       124,070          85,600
Executive Vice President, 
Operations Staff

1.  Includes shares which are subject to outstanding stock options exercisable 
within sixty days of April 30, 1995 as follows:  W. E. Buchholz, 10,000 shares;
P. Dabringhausen 11,300 shares; M. B. Harp, 28,000 shares; E. J. Mooney, 161,000
shares; S. D. Newlin 12,800 shares; J. D. Tinsley, 18,000 shares; W. S. Weeber 
52,000 shares.
2.  Includes shares which may be acquired by exercise of stock options.
3.  Includes beneficial/ownership of shares held indirectly by wife.

Additional Selling Stockholders will be identified by a subsequent appendix. 
One or more of the Selling Stockholders may from time to time make gifts of
any or all of his shares as collateral for loans.  In the event of such gift 
or of a default under any such loan, the donee may elect to sell donated 
shares or the lender may elect to sell shares held as collateral by means of 
the prospectus as supplemented.