Nikolai Vladimirovich Yefimov (Russian: Никола́й Влади́мирович Ефи́мов; 31 May 1910 in Orenburg – 14 August 1982 in Moscow) was a Soviet mathematician.
He is most famous for his work on generalized Hilbert's problem on surfaces of negative curvature.
Yefimov grew up in Rostov-on-Don and graduated from Rostov State University, where he studied with Morduhai-Boltovskoi.
He was an invited plenary speaker at the International Congress of Mathematicians in Moscow, 1966.
He became a corresponding member of the Academy of Sciences of the Soviet Union in 1979.