Julian E. Gillespie Jr., 51, executive vice president of Johnston, Lemon & Co. stock brokerage and investment concern, and a lifelong area resident, died Aug. 7 at Suburban Hospital after a heart attack. He lived in Sumner.

Mr. Gillespie worked for the old Mackall & Coe brokerage firm for 20 years, and rose to its presidency. He joined Johnston, Lemon when it acquired Mackall & Coe about five years ago.

He was a member of the board of governors of both the National Associaton of Securities Dealers and the Chevy Chase Country Club. He served on the board of trustees of the Stone Ridge Country Day School in Bethesda and St. Anselm's Abbey in Washington. He was a member of the University Club and the Society of the Cincinnati.

Mr. Gillespie was a graduate of the Landon School in Bethesda, Washington & Lee University in Lexington, and the Georgetown University's law school. He was a member of the D.C. Bar Association.

Survivors include hiw wife, the former Joan O'Neill, of Sumner; four daughters, Joan O. Gillespie of New York City, and Ellen Clare, Elizabeth P., and Julia Howard Gillespie, all of Sumner; a son, Julian E. III, of Sumner, and two sisters, Mary Critchell and Ann G. Kelly, both of Washington.