Yadegar Mokhammad (Tatar: Yädegär Möxämmäd, Yädkär, Yädegär, [jædeˈɡær mœxæmˈmæt]) (died 1565) was the last khan of the Kazan Khanate, occupying the position from March–October 1552. He was the son of Astrakhan khan Qasim II. Between 1542 and 1550 he was in the service of the Tsardom of Russia. In 1550, he participated in the attack on Kazan and then joined the Nogais.
He was captured in October 1552 when Russian troops took Kazan. In 1553 he converted to Christianity, assumed the name of Simeon Kasayevich and lived in Moscow as a Russian nobleman.