Abstract: Provided are a process chamber cleaning apparatus and method in which the inside of a process chamber may be cleaned without damaging to an inner wall or a component of the process chamber. The process chamber cleaning apparatus comprising: a chamber housing; a substrate support installed inside the chamber housing, supporting a plurality of semiconductor substrates; a gas supply providing process gases; a first gas injector installed inside the chamber housing, connected to the gas supply, injecting etch gas, which is one of the process gases, into the chamber housing; and a controller controlling operations of the gas supply and the first gas injector, wherein the first gas injector injects the etch gas in a direction twisted at a predetermined angle from a central direction of the chamber housing.