Sidakhmet (died 1551) was Bey of the Nogai Horde from 1524 to 1541, succeeding Agish Bey and preceding Mamay Khan. The son of Musa Bey, he dominated his younger brothers and attempted to restrain them from invading Muscovy. He became the ruler of the horde in 1524, but he warred with the descendants of Yamgurchi in Astrakhan and with the Kazakh Khanate. He inflicted a crushing defeat on the Kazakhs in the summer of 1537, killing 40 rival sultans. He was overthrown by Mamay Khan in 1540 and was relegated to be Mamay's second-in-command, and he died in 1551.