Kaykhusraw I (Old Anatolian Turkish: كَیخُسرو or Ghiyāth ad-Dīn Kaykhusraw bin Qilij Arslān; Persian: غياث الدين كيخسرو بن قلج ارسلان‎), the eleventh and youngest son of Kilij Arslan II, was Seljuk Sultan of Rûm. He succeeded his father in 1192, but had to fight his brothers for control of the Sultanate, losing to his brother Suleiman II in 1196. He ruled it 1192-1196 and 1205-1211.

Kaykhusraw married a daughter of Manuel Maurozomes. Manuel Maurozomes would hold the castles of Chonae and Laodicea as a vassal of Kaykhusraw.

In 1192/93, Kaykhusraw returned the Byzantine nobleman, Theodore Mangaphas, to Emperor Isaac II after receiving assurances of Mangaphas treatment. With his brother, Rukn ad-Din Suleiman Shah, quickly advancing towards Konya, Kaykhusraw fled to Constantinople in 1196. He lived in Constantinople from 1197-1203, possibly even being baptised.

After Suleiman's death and Kilij Arslan's ascension to the sultanate, Kaykhusraw forced his way into Konya, removed Kilij from power and was enthroned for a second time.

Kaykhusraw seized Antalya in 1207 from its Niceaen garrison which furnished the Seljuq sultanate with a port on the Mediterranean. It was during this year, Kaykhusraw founded a mosque in Antalya.

Kaykhusraw was killed at the Battle of Antioch on the Meander in 1211. His son Kayqubad I, by Manuel Maurozomes' daughter, ruled the Sultanate from 1220 to 1237, and his grandson, Kaykhusraw II, ruled from 1237 to 1246.

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