Martin Marietta Materials, Inc. Increases Regular Cash Dividend 20 Percent.

RALEIGH, N.C. -- Anne H. Lloyd, Senior Vice President, Chief Financial Officer and Treasurer of Martin Marietta Materials, Inc. (NYSE:MLM), today announced that the Board of Directors has approved a 20 percent increase in the regular quarterly cash dividend to $0.275 (twenty-seven and one-half cents) per share on the Corporation's common stock. This dividend, which represents a cash dividend of $1.10 per share on an annualized basis, is payable September 29, 2006, to shareholders of record at the close of business on September 1, 2006.

Commenting on the dividend increase, Lloyd stated, "We are very pleased that our strong cash position and excellent operating performance have once again provided us the ability to increase shareholder returns through the dividend payout. Our objective continues to be to increase shareholder returns through effective utilization of excess cash. We will continue to evaluate further ways to utilize our cash position to provide benefits to our shareholders, which may include other increases in the dividend, additional capital expenditures on high-return, internal growth projects, voluntary pension plan contributions, and further stock repurchases."

Martin Marietta is the nation's second largest producer of construction aggregates, a leading producer of magnesia-based chemical products and is developing structural composites products for use in a wide variety of industries.