压力管式石墨慢化沸水反应炉（RBMK，俄语：Реактор Большой Мощности Канальный，意思是“大功率管式反应炉”）是一种苏联建造的用于核电站的石墨慢化沸水反应堆，也是目前仍有在运行的最早的反应堆和最早的第二代核反应堆（第一代是那些试验性质的研究用反应堆）。截至2013年，俄罗斯境内仍有11台这种反应堆在运行，但是并没有再新建此类型反应堆的计划（此技术于20世纪50年代发明，现在已被认为过时）并且国际社会上有关于关闭剩余那些反应堆的要求。

RBMK反应堆是苏联核能项目的最高峰，其为一种基于苏联的石墨慢化军事级钚生产反应堆的水冷反应堆。其中的第一台机型，奥布宁斯克核电站的AM-1（Атом Мирный，俄语“和平核能”）可以产生5兆瓦电能，并在1954至1959年间为奥布宁斯克供应电力。

The RBMK (Russian:Реактор Большой Мощности Канальный Reaktor Bolshoy Moshchnosti Kanalnyy, "High Power Channel-type Reactor") is a class of graphite-moderated nuclear power reactor designed and built by the Soviet Union.

The RBMK is an early Generation II reactor and the oldest commercial reactor design still in wide operation. Certain aspects of the RBMK reactor design, such as the positive void coefficient properties, the graphite-tipped control rods and instability at low power levels, contributed to the 1986 Chernobyl disaster, in which an RBMK exploded during a mishandled test, and radioactivity was released over a large portion of Europe. The disaster prompted worldwide calls for the reactors to be completely decommissioned. However, there is still considerable reliance on RBMK facilities for power in Russia. While nine RBMK blocks under construction were cancelled after the Chernobyl disaster, and the last of three remaining RBMK blocks at the Chernobyl Nuclear Power Plant was finally shut down in 2000, as of 2013 there are still 11 RBMK reactors operating in Russia – though all 11 were retrofitted with a number of safety updates.