Badr al-Din Mahmud (1259-1308) was a bey of Karaman Beylik, a Turkoman principality in Anatolia, 14th century.

His father was Karaman Bey, who succeeded his elder brother Güneri in 1300.

After the death of Hethum II in 1307, he took advantage of the weakened Armenian Kingdom of Cilicia and captured some of their territories.

But when Seljuk sultan Mesud II died in 1308, he turned back and saw his chance to capture Konya, the Seljuk capital.

His tomb is in Balkusan village at Ermenek district of Karaman Province.