The AMX 50 (official designation) or AMX-50 was a French heavy tank designed in the immediate post Second World War period. It was proposed as, in succession, the French medium, heavy and main battle tank and incorporated many advanced features. However it was to suffer cancellation in the late 1950s due to unfavourable economic and political circumstances combined with delays in development.

After the war the French Army possessed no modern tanks with a heavy armament. The ARL 44 was being developed, but this vehicle, though to be armed with a powerful 90 mm gun, could hardly be called modern, as its suspension system was obsolete. Therefore already in March 1945 the French industry had been invited to design a more satisfactory vehicle. The same year the AMX company (Atelier de Construction d'Issy-les-Moulineaux) presented its projet 141, a project to build the so-called M 4 prototype, armed with a 90 mm Schneider gun.

The M 4 closely resembled the German King Tiger in general form, though the turret was to be made of welded sections; but to limit the weight to a desired thirty metric tonnes the proportions were rather smaller and the armour had a maximum of just thirty millimetres. Like the later German tanks of the war it had, in this case eight, overlapping road wheels. Part of the project was to study whether a modern torsion bar suspension should be used or the height lowered by ten centimetres through a fitting of leaf or coil springs.