Risaldar Mir Dad Khan Tarin , OBI (died c. 1932), was a native officer of the British Indian Army, who belonged to the Hazara region of the North West Frontier Province (now Khyber Pakthunkhwa in Pakistan). He was the father of former Pakistani president Ayub Khan and his brother Sardar Bahadur Khan
Mir Dad Khan was born into a prominent Hindko-speaking family of the ethnic Pashtun Tareen/Tarin clan, settled in village Rehana in the Haripur District of the Hazara region. After some basic schooling, he decided to enroll as a soldier in the (then) British Indian Army, at quite a young age.
He enlisted as a sowar (mounted trooper) in a cavalry regiment, the 9th Hodson's Horse, in 1887 and after initial training, was posted to duties at Ambala, Punjab. His first participation in a major military campaign was during the Chitral Expedition circa 1895-97. Subsequently, he served in the Tirah Campaign and operations in the Barra Valley, 1897-98. He was promoted Jemadar in 1894 and Risaldar in 1900. Later, between October 1914 and mid-1915, he served along with his regiment in France in World War I.