<SEC-DOCUMENT>0001104659-18-035826-index.html : 20180525
<SEC-HEADER>0001104659-18-035826.hdr.sgml : 20180525
<ACCEPTANCE-DATETIME>20180525060334
ACCESSION NUMBER:		0001104659-18-035826
CONFORMED SUBMISSION TYPE:	SD
PUBLIC DOCUMENT COUNT:		1
<RULE>
<RULE-NAME>13p-1
<ITEM>
<ITEM-NUMBER>1.01
<ITEM-PERIOD>20171231
</ITEM>
</RULE>
FILED AS OF DATE:		20180525
DATE AS OF CHANGE:		20180525

FILER:

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			STEEL DYNAMICS INC
		CENTRAL INDEX KEY:			0001022671
		STANDARD INDUSTRIAL CLASSIFICATION:	STEEL WORKS, BLAST FURNACES  ROLLING MILLS (COKE OVENS) [3312]
		IRS NUMBER:				351929476
		STATE OF INCORPORATION:			IN
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		SD
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-21719
		FILM NUMBER:		18859570

	BUSINESS ADDRESS:	
		STREET 1:		7575 W JEFFERSON BLVD
		CITY:			FORT WAYNE
		STATE:			IN
		ZIP:			46804
		BUSINESS PHONE:		260 459 3553

	MAIL ADDRESS:	
		STREET 1:		7575 W JEFFERSON BLVD
		CITY:			FORT WAYNE
		STATE:			IN
		ZIP:			46804
</SEC-HEADER>
<DOCUMENT>
<TYPE>SD
<SEQUENCE>1
<FILENAME>a18-14213_1sd.htm
<DESCRIPTION>SD
<TEXT>
Document 1 - file: a18-14213_1sd.htm

</DOCUMENT>
</SEC-DOCUMENT>