Shammai (50 BCE–30 CE) is a Jewish scholar of the 1st century, and an important figure in Judaism's core work of rabbinic literature, the Mishnah.

Shammai is the most eminent contemporary and the halakhic opponent of Hillel, and is almost invariably mentioned along with him.

Shammai founds a school of his own, known as the House of Shammai, which differs fundamentally from that of Hillel; and many of Shammai's sayings are probably embodied in those handed down in the name of his school.