航空发动机（Aircraft engine）是指主要用来产生拉力或推力使飞机前进的发动机设备。除了产生前进力外，还可以为飞机上的用电设备提供电力，与为空调设备等用气设备提供气源。

按照工作原理来分，可以将航空发动机分为

按能量形式来分：

An aircraft engine is the component of the propulsion system for an aircraft that generates mechanical power. Aircraft engines are almost always either lightweight piston engines or gas turbines, except for small multicopter UAVs which are almost always electric aircraft.