Hourani was born the son of immigrants from South Lebanon. He studied Philosophy, Politics, Economics and History (with an emphasis on international relations)at the Magdalen College in Oxford. He graduated first in his class in 1936. During World War II, he worked at the Royal Institute of International Affairs and in the office of the British Minister of State in Cairo. After the war he helped prepare the Arab case for the Anglo-American Committee of Inquiry.

In 1948 he started teaching at Magdalen College, St. Antony's College, the start of an academic career which would last the rest of his life. He also taught at the American University of Beirut, the University of Chicago, the University of Pennsylvania, and Harvard, ending his academic career as Fellow of St. Antony's College and Reader in the History of the Modern Middle East at Oxford. Many of the academic historians we find in Universities all over the world today where his students.

As an adult, Hourani converted to Christianity. He married Christine Mary Odile Wegg-Prosser in 1955. He died in Oxford at the age of 77 and was buried at Wolvercote Cemetery in Oxford.