John P. Balster, 79 chairman of the board of the First Federal Federal Savings and Loan Association in Arlington, died Monday at Northern Virginia Doctors Hospital after a long illness.

He had served as president of First Federal from 1966 until February, 1976, when he was elected board chairman. During those years, First Federal became the largest savings and loan association in Northern Virginia and the third largest in the state.

Mr. Balster had served as chairman of the Virginia Savings and Loan League in 1958.

Born in Washington, he was a graduate of National University Law School, now part of George Washington University.

He joined American Security and Trust Co. in 1919, after serving with the Navy in World War I, and was an officer of that firm when he was elected a director of First Federal in 1942.

Mr. Balster left American Security and Trust in 1945 to become secretary and managing officer of First Federal.

A member of the Virginia State Bar, he was also a member and past director of the Arlington Rotary Club and was on the Rotary Foundation Committee. He was a trustee of the First Baptist Church of Clarendon and had served as its treasurer for more than 25 years.

Active in the Masons, Mr. Balster was master of Columbia Lodge No. 285. He was a charter member of Arlington Centennial Lodge No. 81, serving as its first treasurer, a position he held for 22 years. He also was a past worthy patron of Mary Washington Chapter No. 50 of the Eastern Star.

He is survived by his wife, Lillian, of the home in Arlington.