Moktar Ould Daddah (Arabic: مختار ولد داداه, romanized: Mukhtār Wald Dāddāh; December 25, 1924 – October 14, 2003) was a Mauritanian politician who led the country after it gained its independence from France. Daddah served as the country's first Prime Minister from 1957 to 1961 and as its first President of Mauritania, a position he held from 1960 until he was deposed in a military coup d'etat in 1978.

He established a one-party state, with his Mauritanian People's Party being the sole legal political entity in the country, and followed a policy of "Islamic socialism" with many nationalizations of private businesses. In his memoirs, Daddah expressed concern that the issue of slavery in Mauritania could lead to armed conflict that would ultimately destroy the country.

In foreign affairs, he joined the Non-Aligned Movement and maintained strong links with Mao Zedong and the People's Republic of China, but he also accepted Western (especially French) foreign aid. During his presidency, Mauritania saw conflict with the Polisario Front in Western Sahara after working to broker a deal to divide the territory with Morocco.