John Eustace Reynolds, 55, an official of the board of governors of the Federal Reserve System, died Friday at Georgetown University Hospital. He had received kidney dialysis treatment for more than 10 years.

With the federal reserve for 25 years, Mr. Reynolds was counselor in the division of international finance, which he had served earlieras director. He also was associate economist of the federal open market committee.

He was born in Buffalo, N.Y., and grew up in Scarsdale, N.Y. He was a graduate of Phillips Andover and Harvard University, where he was an accompanist to the Harvard Glee Club and a member of Phi Beta Kappa.

His schooling was interrupted in World War II, when he served as an officer with the Army Air Corps Weather Service in Okinawa. He returned to Harvard, and later earned a master's degree there in economics.

Mr. Reynolds worked on the staff of the Bank for International Settlements in Basel, Switzerland, for four years before joining the Federal Reserve Board.

He was a member of the Harvard Club here and sang with the Washington Cathedral Choral Society.

He is survived by his wife, Helen S., and two children, Peter Crawford and Laurie Helen, all of the home in Washington, and his mother, Mrs. Eustace Reynolds, and two sisters, Mr. Ellis Williams and Mrs. William Parker, all of Washington. CAPTION: JOHN E. REYNOLDS