The Ignalina Nuclear Power Plant is a decommissioned two-unit RBMK-1500 nuclear power station in Visaginas Municipality, Lithuania. It was named after the nearby city of Ignalina. Due to the plant's similarities to the infamous Chernobyl Nuclear Power Plant in both reactor design and lack of a robust containment building, Lithuania agreed to close the plant as part of its agreement of accession to the European Union. Unit 1 was closed in December 2004; Unit 2 in December 2009, the plant accounted for 25% of Lithuania's electricity generating capacity and supplied about 70% of Lithuania's electrical demand, was closed on December 31, 2009. Proposals have been made to construct a new nuclear power plant at the site, but such plans have yet to come to fruition.

The RBMK is a class of graphite-moderated nuclear power reactor designed and built by the Soviet Union. It is somewhat like a Boiling water reactor as water boils in the pressure tubes. It is one of two reactor types to be developed in the Soviet Union during the 1970s, the other being the VVER reactor. The name refers to its design where instead of a large steel pressure vessel surrounding the entire core, the core is surrounded by a cylindrical annular steel tank inside a concrete vault and each fuel assembly is enclosed in an individual 8 cm (inner) diameter pipe. The channels also contain the coolant, and are surrounded by graphite.