Mohamed Bensaid Ait Idder (Berber languages: ⵎⵓⵃⴰⵎⴷ ⴱⴻⵏⵙⵄⵉⴷ ⴰⵢⵜ ⵉⴷⴷⴻⵔ, Arabic: محمد بنسعيد آيت يدر, 1 July 1925 – 6 February 2024) was a Moroccan politician and activist.

[1] In 1955, Bensaid Ait Idder joined the Moroccan Army of Liberation in the south, participating in armed resistance against French and Spanish forces in Morocco.

In 1959, Ait Idder, along with several modernist activists, left the Istiqlal Party and helped create the National Union of Popular Forces.

Following the 1965 Moroccan riots, Ait Idder and other Marxist–Leninist activists founded Harakat 23 Mars, a movement that spread revolutionary ideas in Morocco.

[2] In 1981, Ait Idder received a royal pardon and returned to Morocco, where he founded the legal Organization for the Popular Democratic Action party.