Sheelagh Perry, 35, the legislative assistant of Rep. Jonathan B. Bingham (D-N.Y.) and a congressional aide since 1966, died of a brain tumor Wednesday at Alexandria Hospital.

Miss Perry, who lived in Arlington, began her career on Capitol Hill in October 1966, when she joined the staff of former Sen. Joseph S. Clark (D-Pa.). She moved to Bingham's office in March 1967, and remained there until her death. She had been the congressman's legislative assistant for the last six years.

In addition to her work with Congress, Miss Perry was active in politics. She worked in the campaign of President Carter in 1976 and for Sen. Edward M. Kennedy (D-Mass.) in his unsuccessful effort to win the Democratic presidential nomination this year. She was a staff assistant at the Democratic National Convention in New York City last summer.

Miss Perry also was a member of the World Future Society.

A native of Charlottesville, Miss Perry grew up in Alexandria and Fayetteville, N.Y. She attended Ohio Wesleyan University and earned a bachelor's degree in political science at American University.

Survivors include her parents, Mr. and Mrs. Elmer Perry of Charlottsville, and a brother, Dr. Christopher Perry of Boston, Mass.