Yaakov ben Yakar (990 - 1064) was a German Talmudist. He flourished in the first half of the 11th century. He was a pupil of Gershom ben Judah in Mainz, and is especially known as the teacher of Rashi, who characterizes him as Mori HaZaken (my teacher the elder).

Yaakov was one of the leading Talmudic authorities of his time. In some cases Rashi disagrees with the opinions of his teacher Yaakov.