Nikolay Vladimirovich Davydenko (Russian: Николай Владимирович Давыденко; born June 2, 1981 in Severodonetsk, Ukrainian SSR, Soviet Union) is a Russian tennis player of Ukrainian descent. He is, as of July 27, 2009, the top ranked male player for Russia and 9th in the world.

Davydenko's best result in a Grand Slam tournament has been reaching the semi-finals, which he has done on four occasions - twice each at the French Open and the U.S. Open.

Davydenko was born on June 2, 1981, in Severodonetsk, Ukraine to Vladimir and Tatyana. At the age of 11, Nikolay left his parents in Ukraine to live with his elder brother Eduard in Volgograd, Russia in the belief that Russia would afford more opportunities to become a professional tennis player.