Dr. Abram Leon Sachar, a historian who led the Hillel Foundation for 22 years and was the founding president of Brandeis University in Waltham, Mass., died yesterday at his home in Newton, Mass. He was 94.

The cause of death was respiratory failure, according to Dennis Nealon, a spokesman for the university.

Mr. Sachar was widely regarded as the driving force behind the development of Brandeis into a major research institution.

When it opened under his direction in 1948, Brandeis had 107 students and 13 faculty members. Today it has 3,700 undergraduate and graduate students, and a full-time faculty of 360.

During his 20 years as president, Dr. Sachar, whom friends described as having an "edifice complex," raised $250 million for the school and saw the campus grow from a few buildings on the site of a bankrupt medical school to a complex of 90 buildings on 235 acres. He subsequently assumed the post of chancellor of the university, serving as a sort of roving ambassador for the institution.

Dr. Samuel O. Thier, the president of Brandeis, praised Dr. Sachar's contributions, saying his "vision and skill in creating Brandeis are unparalleled in higher education."

Dr. Sachar served on numerous Federal panels, including the United States Holocaust Commission, and the Advisory Commission on International Education and Cultural Affairs.

Dr. Sachar was born in New York on Feb. 15, 1899, to immigrant parents. His father, Samuel, was born in Lithuania; his mother, Sarah Abramowitz, was born in Jerusalem.

When he was 7 his family moved to St. Louis, where he attended Washington University, receiving bachelor's and master's degrees in history. He received a doctorate in history from Cambridge University in 1923.

Returning to the United States, Dr. Sachar joined the history faculty of the University of Illinois where he remained for 24 years. While there he became a leader of the Hillel Foundation, which was founded there. He served as director of the National Hillel Foundation from 1933 to 1948, and as chairman from 1948 to 1955, before retiring to become president of Brandeis.

Dr. Sachar was the author of several books, including "The Course of Our Times"; "A History of the Jews"; "The Redemption of the Unwanted"; "Factors in Jewish History"; "Sufferance is the Badge" and a history of Brandeis, titled "A Host At Last."

Heis survived by his wife of 67 years, Thelma Horowitz; two sons, Dr. David B. Sachar of Englewood Cliffs, N.J., and Howard M. Sachar of Kensington, Md.

Photo: Dr. Abram Leon Sachar (Associated Press, 1976)