Muhammad Ayub Khan was born on May 14, 1907, in the village of Rehana near Haripur, in Hazara District. He was the first child of the second wife of Mir Dad Khan, who was a Risaldar Major in Hodson's Horse. According to Ayub, his father had the greatest influence on his character, outlook, and attitude towards life. For his basic education, he was enrolled in a school in Sarai Saleh, which was about 4 miles from his village. He used to go to school on a mule's back. Later he was shifted to a school in Haripur, where he started living with his grandmother. As a child he was interested in playing kabaddi, gulli danda, marbles and hockey. After passing his Matriculation Examination in 1922, Ayub was sent to Aligarh University where he spent four years. However, before appearing in his B. A. exams, he was selected for the Royal Military College at Sandhurst. He sailed for England in 1926.

Ayub's performance in Sandhurst was exemplary and he won several scholarships. After the completion of training, he got commissioned in the Indian Army in 1928. He fought at different fronts during World War II, first as a Major and then Colonel. During the communal riots of 1947, he was assigned to assist General Pete Rees in the Punjab Boundary Force. At the time of Independence, Ayub Khan opted to join the Pakistan Army, where as a Brigadier, he was the senior-most Muslim officer. In 1951, he was raised to the status of a four-star General and was appointed as the first local Commander-in-Chief of the Pakistan Army.