Yousuf Shah Chak (Urdu; یُوسف شاہ چک Hindi: काम्बोज राजा यूसुफ चक ) was a Kamboj ruler of Kashmir. He was the successor of his father Ali Shah Chak and ruled Kashmir from 1579 to 1586 AD. The Chaks were religiously divided between the main Sunni segment of the tribe led by Regi Chak and Shams Chak, and Nurbakhshiya Sufis, which some have described as an offshoot of Shiism. While smaller in number, their Nurbakshiya Sufi Chaks included the leaning of Ghazi Shah Chak, Ali Shah Chak, and the Yousuf Shah Chak. They were formidable and ferocious fighters of huge structure and soundly defeated the great Mughal Emperor Akbar twice and that too with a much smaller army. Some disgruntled Kashmiri nobles were often pushing Akbar to annex Kashmir.
Yousuf Shah Chak sought refuge in Sialkot before he was brought to Delhi for talks with Akbar. Akbar's forces betrayed Yousuf and imprisoned him for the rest of his life. It is narrated that Habba Khatoon, Yousuf's love interest and a well-known poetess of Kashmir, had opposed Yousuf's travel to Delhi, for she sensed Akbar's offer as bait. She later made mention of this in her writings. Chaks successfully resisted the attempts of Babur and Humayun to annex Kashmir.
Yusuf was succeeded by his son Yakub Shah Chak (a great warrior as well) who ruled Kashmir for three years until 1589 AD when it was annexed to Mughal Empire by Akbar.
Yousuf was jailed in Bengal and later shifted to Bihar where he died. His grave remains in Bihar buried in village Biswak (District Nalanda).
King Yousuf Chak is a well-known clan among the modern Kamboj. The Chaks of Kashmir are not its original inhabitants but are known to have migrated there from Daradistan. Since in ancient times, the Daradas and Kambojas were next-door neighbors in the cis-Hindukush region, it is very likely that Yusuf Chak, the ruler of Kashmir and his dynasty, could be traceable to an ancient clan of the Kambojas living as neighbors to the Daradas in/around Kashmir. It is a known fact of history that ancient Kambojas had ruled over Kashmir during and prior to epic times. So, it is very possible that the Chaks of Kashmir may not be of Daradic origin but rather may have come from Kamboja background.