World revolution is a Marxist concept of a violent overthrow of capitalism that would take place in all countries simultaneously.

While not actually part of a World Revolution, this iconic World War II image shows Berlin falling to the Red Army on 2 May. Here, the Hammer and Sickle is flown over the Reichstag - an inspiring image for socio-communists.

Arguably, the international situation in the years immediately following World War I was the closest the world ever came to such a revolution. The October Revolution of 1917 in Russia sparked a wave of socialist and communist uprisings across Europe, most notably the German Revolution and the Hungarian Revolution, which made large gains and met with considerable success in the early stages. Particularly in the years 1918-1919, it seemed plausible that capitalism would soon be swept from the European continent forever. Given the fact that European powers controlled the majority of Earth's land surface at the time, such an event could have meant the end of capitalism not just in Europe, but everywhere.

With the prospect of world revolution so close at hand, communists, socialists and workers' movements in general were dominated by a feeling of overwhelming optimism, which in the end proved to be quite premature. The European revolutions were crushed one by one, until eventually the Russian revolutionaries found themselves to be the only survivors. Since they had been relying on the idea that an underdeveloped and agrarian country like Russia would be able to build socialism with help from successful revolutionary governments in the more industrialized parts of Europe, they found themselves in a crisis once it became clear that no such help would arrive (see Socialism in one country).

After those events and up until the present day, the international situation never came so close to a world revolution ever again.

Within Marxism, Lenin's detailing of Marx's concept of the labor aristocracy, as well as Lenin's description of imperialism and Trotsky's theories regarding the corruption of the Soviet Union under Stalinism, offer several explanations regarding why the world revolution did not occur up to the present day.

In the worlds described in Soviet science fiction , the world revolution usually has already taken place.

A British communist group is called World Revolution.