Nawab Mir Yousaf Aziz Magsi (born 1908 in Jhal Magsi, Pakistan-May 31, 1935) was a prominent Baloch leader from the present-day Balochistan province of Pakistan. He hailed from the Magsi tribe headquartered in Jhal Magsi, the ancestral home of the Magsi. His title was Nawab, which means "ruling prince" or "tribal chief". His father, Kaiser Khan Magsi, was the Nawab of the Magsi tribe.
Mir Yousaf Khan obtained his education at home. He was able to master Arabic, Persian and Urdu within a few years. Then he was taught English by a private tutor for two years.
In 1922, because of some family problems Yousaf Magsi's father Nawab Kaiser Khan and Yousaf himself had to go into exile in Multan. Yousaf Khan stayed in exile in Multan until 1929.
Mir Yousaf Ali Khan was impressed by the revolutionary atmosphere of Punjab and was drawn toward the Indian National Congress' struggle for independence from British rule. He was filled with a desire to launch a similar struggle in Balochistan. His first step in this regard was an article he wrote, titled "Balochistan Kee Faryaad" or "Balochistan's Lament", which was published in a weekly newspaper, Hamdard, on November 17, 1929. As a result of this article, a special Jirga held in Kalat on July 17, 1930 sentenced Mir Yousaf Ali Khan to one year of solitary confinement in Zehri and an 11,000-rupee fine. Magsi also published the pamphlet Baluchistan Kee Awaz (Voice of Baluchistan), which was sent to the British parliament to raise awareness of his cause.
During the proceedings of the above-mentioned Jirga, Mir Yousaf Ali Khan was held in Mastung Jail. While he was in jail, members of a clandestine political party (Anjuman-i-Ithihaad i Balochaan), who were also deeply impressed by the struggle of the Indian National Congress, contacted Yousaf Ali Khan. They helped him during his solitary confinement. In 1931, after completing his sentence, Mir Yousaf Ali Khan came to Quetta where, along with Mir Abdul Aziz Kurd, Nawabzada Mir Abdul Rehman Bugti, Mohammad Hussain Unqa, Malik Faiz Mohammad Yousafzai and others, he officially announced the Anjuman-i-Ithihaad i Balochaan as a political party. Mir Abdul Aziz Kurd was elected as the General Secretary of the party while Mir Yousaf Ali Khan became its President. The Prime Minister of Kalat issued orders to arrest Yousaf Ali Khan once again but Yousaf somehow learned about the plan to arrest him beforehand, so he went and took refuge in Jacobabad, where he started his famous Magsi Agitation.