Ausubel was born in Lezajsk, Galicia, the sixth of eight children, and immigrated with his family to New York City in 1907, where he later attended Columbia University. Ausubel enlisted in the Jewish Legion's 39th Battalion during World War I and fought in the Jordan Valley.

He was married to Marynn Ausubel (1913—1980) and had one daughter, Ethel Frimmet. His cousin, Dr. Herman Ausubel, was a professor of Victorian history at Columbia, and his nephew David P. Ausubel was a noted professor, educator, ethnographer, and a pioneer in cognitive educational psychology.

Ausubel is best known for his two books, A Treasury of Jewish folklore, which went through over twenty editions, and Pictorial History Of The Jewish People, which included detailed descriptions of previously unknown Lost Tribes of Israel, as well as information on the Khazars. A partial bibliography follows:

• Superman; The Life Of Frederick The Great, I. Washburn, 1931.
• A Treasury Of Jewish Folklore; Stories, Traditions, Legends, Humor, Wisdom And Folk Songs Of The Jewish People (originally published 1948), Crown Publishers, 1989 ISBN 0-517-50293-3
• Jewish culture in America: Weapon for Jewish survival and progress, New Century Publishers, 1948.
• Pictorial History Of The Jewish People, From Bible Times To Our Own Day Throughout The World (originally published 1953), Crown Publishers, 1984. ISBN 0-517-55283-3
• The Book of Jewish Knowledge;: An encyclopedia of Judaism and the Jewish people, covering all elements of Jewish life from Biblical times to the present, Crown Publishers, 1964. ISBN 0-517-09746-X
• A Treasury of Jewish Poetry, 1970.
• A Treasury of Jewish Humor, (originally published 1951), M. Evans and Company, 1988. ISBN 0-87131-546-7

Ausubel translated several works of Yiddish literature, most notably Mother, by Sholom Asch. He also co-edited the annual series Voices of history.

"Jews have received their tempering from an unflinching realism learned for a high fee in the school of life; they have always felt the need of fortifying their spirits with the armor of laughter against the barbs of the world."- A Treasury Of Jewish Folklore, 1948.

"[Folklore is a true and unguarded portrait, for where art may be selective, may conceal, may gloss over defects and even prettify, folk art is always revealing, always truthful in the sense that it is spontaneous expression."- A Treasury Of Jewish Folklore, 1948.

"First you laugh at a Jewish joke or quip. Then, against your will, you suddenly fall silent and thoughtful. And that is because Jews are so frequently jesting philosophers. A hard life has made them realists, realists without illusion." - A Treasury of Jewish Humor, 1951.

"Of all the astonishing experiences of the widely dispersed Jewish people none was more extraordinary than that concerning the Khazars."- Pictorial History of the Jewish People, 1953.