Nathan T. (Nate) Wolkomir, 69, a retired president of the National Federation of Federal Employees (NFFE) who was known as a fierce supporter of the "little people" in government, died Wednesday at Doctor's Hospital after a heart attack.

Mr. Wolkomir spent 23 years in government management, mostly as an Air Force civilian in New York and Illinois, before his election in 1964 as president of the traditionally conservative NFFE, the oldest general membership federal union. He was reelected by acclamation at succeeding conclaves until his retirement in 1976.

He was credited with changing the union's ultraconservative image -- its members once objected to its being called a union and, until his election, had opposed and boycotted presidential efforts for union recognition -- by taking full advantage of President Johnson's labor-management order permitting employe unions to be recognized and to negotiate working agreements with federal agencies.

In 1969 Washington Post interview, Mr. Wolkomir compared the federal employe to a "microscopic ant who gains influence only in numbers, through organization." He further asserted that the reason government union exist and keep growing is that "government personnel officers and the Civil Service Commission, which are supposed to be the buffers between employes and management, are a fraud . . . and represents management only. Nobody represents employes but the union."

Mr. Wolkomir, on the other hand, opposed any liberalization of the Hatch Act. He said the only those federal employes who fail to register and vote and to make their views known on the issues of the day are in the "second-class citizen category" often referred to by those opposed to the Hatch Act.

In 1975, he opposed, along with other federal union leaders, the Rockfeller pay plan proposal which called for automatic pay raises based on time-in-grade service. It would have split professional and clerical employes into two pay systems that, he claimed, "would only create needless class distinctions and would probably result in higher administrative costs."

The plan was subsequently defeated but the Carter administration still is proposing similar legislation.

Mr. Wolkomir was born in Baku, Russia, and came to this country with his family as an infant. He earned bachelor's degrees from St. Francis College and New York University and master's degrees and a doctorate in educational psychology from St. John's University and the University of Illinois.

He was a playwright and author and often lectured on labor-management relations at seminars throughout the country.

Mr. Wolkomir was a member of numerous professional organizations and had served on the President's Committee for Employment of the Handicapped. He was a 32nd Degree Scottish Rite Mason and a member of the Almas Temple Shrine, the Kiwanis International, the Odd Fellows and the Air Force Association.

Survivors include his wife, Louise, of the home in Wheaton; two daughters, Rhya McCulloch, of Woodbridge, and Diane Atkinson, of Rantoul, Ill.; a son Darwin J., also of Rantoul; a brother, Benjamin, of Athens, N.Y., and 12 grandchildren.

The family suggests that expressions of sympathy be in the form of contributions to the Children's Hospital National Medical Center, St. Mary's Hospital in Rochester, Minn., or to the Mayo Lung Project at the Mayo Clinic in Rochester.