Walter N. Tobriner, 77, who served as the last president of the D.C. Board of Commissioners before it was ended in a major reorganization of the city government in 1967, died yesterday at his home in Washington. He had cancer.

He had held the job for 6 1/2 years during a period of great tension in the nation's capital, particularly in the area of civil rights. He faced those difficulties by leading the way in bringing about fair housing and fair employment regulations.

Before serving as a D.C. commissioner, Mr. Tobriner had held another vital city position, that of president of the Board of Education during the crisis that followed the Supreme Court's 1954 ruling ordering desegregation of public schools.

He was credited with quietly guiding the schools through the transition with strength and statesmanship.

After his service with the D.C. government, Mr. Tobriner served for nearly two years as U.S. ambassador to Jamaica. He resigned from that position in March 1969.

He then returned to private life and his practice of corporate and probate law in Washington, which he maintained until his death.

A tall, slender, slightly baldish man, the softspoken Mr. Tobriner did not seek high positions in government.

But he was full of ideas on how to create a better city, and gradually he became involved. He once explained why.

"My family's prospered here, I've been here a hell of a long time and felt I owed something to the town."

He always denied that he was a politician, even declaring, "I hate politics; can't stomach it." But he was active for many years in the Democratic Party, serving as a delegate to three national conventions+.

He began his law practice here in 1927, and eventually law a lw professor at the National Law School. He also started to speak out on civic matters.

Mr. Tobriner was appointed a member of the school board in 1952. At that time board members were appointed by a panel of District Court judges. Since 1968, they have been elected.

An early proponent of civil rights, the new board member in 1952 saw school desegregation coming and urged that the city school system prepare for it. He played a leading role in bringing about desegregation peacefully, trying to make the school system live up to expectations that the nation's capital serve as an example for the entire country.

He continued in that role after he became school board president in 1957. When President Kennedy appointed him to the Board of Commissioners in 1961, the appointment was lauded as "admirable on two counts," by The Washington Post.

"It honors a Washingtonian who has served his community with exceptional ability and devotion: and it gives this colonial dependency of the United States a native-born governor sympathetic to its aspirations and exceptionally qualified to advance them," The Post said.

President Johnson reappointed Mr. Tobriner to the Board of Commissioners in 1964. Again the action was lauded. It was noted that Mr. Tobriner in his first term had brought significant gains in political freedom here (He had always been a strong advocate of some form of home rule for the city.)

As the commissioner in charge of the police department, he had ended a police practice of making arrests for investigations without probable cause to justify them.

Mr. Tobriner stood firmly behind the police but was just as firm in his belief that they must adhere to the Constitution. Later, in 1966 during his second term, he backed a special crime commission whose recommendations resulted in a major shakeup in the police department.

In 1964, Mr. Tobriner also brought about a fair housing ordinance, and a year later, a fair employment ordinance, both aimed at ending racial discrimination.

He favored a civil rights unit tht e city's legal office. He was an early proponent of a two-year community college for vocational studies and a four-year community college for liberal arts.

Mr. Tobriner was chairman of the Washington Metropolitan Area Transit Authority in 1966-67, when the first contracts were awarded for the subway system here.

He was a trustee of the National Cultural Center during 1964-67, when plans were drafted for the John F. Kennedy Center for the Performing Arts.

He was the arbiter at hearings, not only on major matters but on trivia as well. And during all those busy days, he worked without stint for a more modern form of government for the city, which he knew would take away his job as commissioner.

The new form of government went into effect in 1967, replacing the three-member Board of Commissioners with a single White House-appointed commissioner and a nine-member City Council.

He was the first to wish the city fathers success but he also warned them of pitfalls. "The commissioner is the well known guy who's in the middle - who has responsibility without authority," he said.

Between the president who appoints him and the Congress, which still rules the city and cane "make a monkey out of him," are the people and their problems," he added.

But Mr. Tobriner favored the change, because he believed a single commissioner could be more effective and a city council with nine members more receptive to the public.

Commissioner-Mayor Walter E. Washington was the first appointee under the city's new form of government. Since 1974, the mayor and City Council have been elected.

Walter Nathan Tobriner was born in Washington on July 2, 1902. he attended Friends School here, but left at the end of the 11th grade to enter Princeton University. (Many years later, Friends School presented him with a diploma.) He earned his law degree at Harvard in 1926.

In 1933, he married Marienne Elizabeth Smith.

During World War II, Mr. Tobriner served as a legal officer with the Army Air Forces.

From 1952 to 1955 he was board president of the old Garfield Memorial Hospital, and from 1959 to 1961, he headed the board of the Washington Hospital Center. He was board director of the Blue Cross Plan from 1953 to 1961.

He was named board president of the Lisner Home, a charitable home for women in Washington, in 1954, and was still on the board at his death.

Since 1974, Mr. Tobriner had been a member of the Committee of 100 on the Federal City.

He belonged to Phi Beta Kappa, the National Capital Democratic Club and the Cosmos Club.

In addition to his wife, of the home, he is survived by a son, Matthew W., of Bethedda; a daughter, Constance E. Povich, of Washington; a brother Ralph Z., of El Paso, Tex., and six grandchildren.

The family suggests that expressions of sympathy be in the form of contributions to the Lisner Home or the Washington YWCA. CAPTION: Picture, WALTER N. TOBRINER