Nechama Leibowitz was born to an Orthodox Jewish family in Riga two years after her elder brother, the philosopher Yeshayahu Leibowitz. The family moved to Berlin in 1919. In 1930, Leibowitz received a doctorate from the University of Marburg for her thesis, Techniques in the Translations of German-Jewish Biblical Translations. That same year 1930, she immigrated to Mandate Palestine. She taught at a religious Zionist teachers' seminar for the next twenty-five years. In 1957 she began lecturing at Tel Aviv University, and became a full professor eleven years later. She also gave classes at the Hebrew University of Jerusalem and other educational institutions around the country. In addition to her writings, Leibowitz commented on the Torah readings regularly for the Voice of Israel radio station.
She married her uncle, Yedidya Lipman Leibowitz. They had no children. She is seen as a great religious role model for young religious children in Israel, and the Ne'emanei Torah Va'Avodah organization has encouraged the public school system in Israel to incorporate her into the selection of biographies that are studied by Israeli children in primary schools.
In 1942, Leibowitz began mailing out stencils of questions on the weekly Torah reading to anyone who requested them. These worksheets, which she called gilyonot (pages) would be sent back to her, and she would personally review them and return them with corrections and comments. They became very popular and in demand by people from all sectors of Israeli society. In 1954, Leibowitz began publishing her "Studies", which included many of the questions that appeared on her study sheets, along with selected traditional commentaries and her own notes on them. Over time, these studies were collected into five books, one for each book of the Torah. These books were subsequently translated into English by Rabbi Dr. Aryeh (Laibel/Leonard) Newman.
When asked to describe her methods she replied, "I have no derech... I only teach what the commentaries say. Nothing is my own."  She was noted for her modest demeanor coupled with wry wit, and always preferred the title of "teacher" over the more prestigious "professor." In accordance with her request, "?" (morah, "teacher") is the only word inscribed on her tombstone, other than her name and dates. She was strict on marking mistakes in Hebrew test papers, and hated the code-switching "Heblish" of some anglophone immigrants.