Yadegar Mokhammad (Volga Türki and Persian: یادگار محمد; Tatar: Yädegär Möxämmäd, Yädkär, Yädegär, [jædeˈɡær mœxæmˈmæt]) (died 1565) was the last khan of the Kazan Khanate, occupying the position from March to October 1552.

After the Kazan Khanate was nearly brought to defeat by Ivan the Terrible's forces in 1550, in 1551 the "peace party" in Kazan enthroned the pro-Russian khan Shah Ali.

Shah Ali fled and Yadegar was invited by Qol Sharif and Chapqin bek Otich uli (Çapqın bäk Otıç ulı, [ɕʌpˈqɯn bæk ɔˈtɯɕuˈlɯ]) to the throne of the Kazan Khanate.

Subsequently, he led the war against the Russian invasion (see Siege of Kazan).

In 1553 he converted to Christianity, assumed the name of Simeon Kasayevich and lived in Moscow as a Russian nobleman.