2009-10-27 13:50:10 -

Martin Marietta Materials, Inc. (NYSE:MLM) today announced that it will provide an online Web simulcast of its third-quarter 2009 earnings conference call on Tuesday, November 3, 2009. The Company will release results for the third quarter and nine months ended September 30, 2009, that morning before the market opens.

The live broadcast of Martin Marietta Materials' conference call will begin at

2:00 p.m. Eastern Time on November 3, 2009. An online replay will be available approximately two hours following the conclusion of the live broadcast and will continue for one year. A link to these events is available at the Company's website: www.martinmarietta.com : .

For those investors without online web access, the conference call may also be accessed by calling 913-312-0648, confirmation number 4514897.

Martin Marietta Materials is a leading producer of construction aggregates and a producer of magnesia-based chemicals and dolomitic lime.

MLM-G


Martin Marietta Materials, Inc.Anne Lloyd, 919-783-4660Executive
Vice President, Chief Financial Officer and Treasurer www.martinmarietta.com :