Baiju Noyan or Baichu (Mongolian: ᠪᠠᠶᠢᠵᠤ ᠨᠣᠶᠠᠨ; Chagatai: بایجو نویان; Chinese: 拜住; pinyin: Bàizhù; in European sources: Bayothnoy; fl.

Baiju immediately moved against the Seljuk Sultanate of Rûm, weakening its power at the Battle of Köse Dağ on 26 June 1243.

Embassy's disrespect and Ascelin's refusal to triple genuflection angered Baiju, he insulted the pope and demanded his submission as well.

Baiju was supposedly reproached by Hulegu for failing to extend Mongol power further, and, indeed, was replaced by him as supreme commander as early as 1255, but served under him ably in further campaigns: against the Sultanate of Rum (to extract tribute and replace the sultan Kaykavus II) in 1256, in the assault on Baghdad in 1258, and in the advance on Syria towards Egypt[citation needed] in September 1259.

According to various sources Baiju was executed by Hülegü after the capture of Baghdad due to his hesitation to join Hulagu during the campaign and his secret correspondence with Caliph Al-Musta'sim.