Venera 3 (Russian: -3 meaning Venus 3) was a Venera program space probe that was built and launched by the Soviet Union to explore the surface of Venus. It was launched on 16 November 1965 at 04:19 UTC from Baikonur, Kazakhstan, USSR. The probe comprised an entry probe, designed to enter the Venus atmosphere and parachute to the surface, and a carrier/flyby spacecraft, which carried the entry probe to Venus and also served as a communications relay for the entry probe.

The Venera (Russian: Вене́ра, pronounced [vʲɪˈnʲɛrə], which means "Venus" in Russian) program was the name given to a series of space probes developed by the Soviet Union between 1961 and 1984 to gather information about the planet Venus. Ten probes successfully landed on the surface of the planet, including the two Vega program and Venera-Halley probes, while thirteen probes successfully entered the Venusian atmosphere. Due to the extreme surface conditions on Venus, the probes could only survive for a short period on the surface, with times ranging from 23 minutes to two hours.

The Venera program established a number of precedents in space exploration, among them being the first human-made devices to enter the atmosphere of another planet (Venera 3 on 1 March 1966), the first to make a soft landing on another planet (Venera 7 on 15 December 1970), the first to return images from another planet's surface (Venera 9 on 8 June 1975), the first to record sounds on another planet (Venera 13 on 30 October 1981), and the first to perform high-resolution radar mapping scans (Venera 15 on 2 June 1983).