Abstract: A process for treating aged oil by electron beam irradiation is disclosed, comprising the following steps: step 1, homogenizing the aged oil and then feeding the aged oil into a distributor; step 2, forming a liquid layer having a certain thickness on the distributor; step 3, installing and debugging an electron beam irradiation device on the distributor; step 4, installing and debugging a phased-array microwave emitter on the distributor after installing and debugging the electron beam irradiation device; step 5, turning on the electron beam irradiation device and the phased-array microwave emitter; and step 6, dividing the treated aged oil and then allowing the aged oil after dividing to enter an oil pool and a water pool for standing. Oil flows out from an upper layer of the oil pool, a lower layer of the oil pool flows back to an aged oil storage pool.