June 24, 2008

Reliance Steel & Aluminum Co. Updates 2008 Second Quarter Outlook

Reliance Steel & Aluminum Co. (NYSE:RS) announced today that it is updating its guidance regarding the Company's earnings estimates for the second quarter ended June 30, 2008. At this time, Reliance expects earnings to be in the range of $2.00 to $2.10 per diluted share, up approximately 30% from the Company's prior guidance. The current mean of the Wall Street analysts' earnings estimates for Reliance's 2008 second quarter is $1.63 per diluted share.

Reliance's Chairman and Chief Executive Officer, David H. Hannah, said, "In our April 17, 2008 first quarter press release we included an estimate for our 2008 second quarter earnings of $1.50 to $1.60 per diluted share. Because the prices for carbon steel products have increased more significantly and more rapidly than we had anticipated and because we have been successful in expanding our gross profit margins more than anticipated in the current environment, we have increased our earnings guidance. The updated guidance includes a LIFO estimate of $100 million for the year, up from our prior estimate of $70 million. This results in a second quarter LIFO expense of $32.5 million compared to $17.5 million included in our prior guidance. As a result, we have updated our earnings guidance to reflect our current expectations."

The Company will announce its financial results for the three and six months ended June 30, 2008 on Thursday, July 17, 2008 prior to the opening of the New York Stock Exchange and will host a conference call web cast that same day at 11:00 a.m. Eastern Time at: www.rsac.com/investorinformation.

Reliance Steel & Aluminum Co., headquartered in Los Angeles, California, is the largest metals service center company in the United States. Through a network of more than 180 locations in 37 states and Belgium, Canada, China, South Korea and the United Kingdom, the Company provides value-added metals processing services and distributes a full line of over 100,000 metal products. These products include galvanized, hot-rolled and cold-finished steel; stainless steel; aluminum; brass; copper; titanium and alloy steel sold to more than 125,000 customers in various industries.

Reliance Steel & Aluminum Co.'s press releases and additional information are available on the Company's web site at www.rsac.com. The Company was named to the 2007 "Fortune 500" List and the Fortune 2007 "100 Fastest Growing Companies" List and the Fortune 2008 List of "America's Most Admired Companies" the 2008 Forbes "America's Best Managed Companies" List, and the 2008 Forbes "Platinum 400 List of America's Best Big Companies."

This release may contain forward-looking statements relating to future financial results. Actual results may differ materially as a result of many factors over which Reliance Steel & Aluminum Co. has no control. These risk factors and additional information are included in the Company's Annual Report on Form 10-K for the year ended December 31, 2007 and other reports the Company has on file with the Securities and Exchange Commission.