He worked to persuade Hussein bin Ali, the Sharif of Mecca to break with the Ottoman Empire and join the Allies.

During the Occupation of France in World War II, he hid and saved numerous Jews in the basements of the Grand Mosque of Paris.

Alongside Abdelkader Mesli, he joined the resistance and protected numerous victims of persecution, sometimes estimated to have been more than one thousand persons.

After his secondary education at the Madrasa Thaalibia in Algiers and the University of al-Karaouine of Fez, he started his career in Algeria, in the field of judiciary.

[6] The American historian Ethan Katz described Benghabrit as bicultural, a man who was equally comfortable with both aspects of his identity as French and Muslim who "moved seamlessly" between the cultural worlds of France and the Maghreb.

[6] In 1892, he became assistant interpreter at the Legation of France to Tangier; he served as a liaison between North African officials and the French Ministry of Foreign Affairs.

[13] For the most part, French Muslims remained loyal to the republic during World War One and disregarded the Ottoman declaration of jihad, which improved his standing in Paris.

[13] In 1916, France sent him to Hijaz as head of the French diplomatic mission to Mecca to facilitate the Hajj and ensure the well-being of his fellow citizens during their time in the holy places of Islam, and to convince Hussein bin Ali, the Sharif of Mecca to break with the Ottoman Empire and join the Allies,[10] assuring him of French support for a caliphate headed by himself.

[18] In 1917, Si Kaddour founded in the Mahkama of Algiers (civil court or qadi), the Society of Habous and the Holy Places of Islam, in order to facilitate the pilgrimage to Mecca by Muslims from French North Africa.

At the opening of the Great Mosque, Benghabrit in his speeches in both French and Arabic praised the "eternal union" of France and Islam.

[21] Also he saved the lives of at least five hundred Jews, including that of the Algerian singer Salim Halali, making the administrative staff grant them certificates of Muslim identity, which allowed them to avoid arrest and deportation.

On the other hand, Alain Boyer, former head of religious affairs in the French Ministry of Interior, has stated that the number was closer to 500 people.

The Bâtisseuses de Paix, an association of Jewish and Muslim women working for inter-community harmony, submitted a petition in 2005 to Yad Vashem's Council to recognize that the Mosque of Paris saved many Jews between 1942 and 1944, and that Yad Vashem should thus recognize Si Kaddour Benghabrit as one of the Righteous Among the Nations.

Nouria Benghabrit-Remaoun, sociologist and researcher, granddaughter of Si Kaddour Benghabrit's brother, was the Minister of National Education of Algeria.