The invention discloses a solar offshore fishery functional three-body unmanned ship with side bodies capable of floating and diving. The solar offshore fishery functional three-body unmanned ship comprises a main ship body, the first side sheet body and the second side sheet body, wherein the first side sheet body and the second side sheet body are symmetrical in structure and are located on thetwo sides of the main ship body correspondingly. The first side sheet body and the second side sheet body are connected with a first driving device and a third driving device correspondingly. The first driving device and the third driving device are the same in structure and are symmetrically arranged on the left side and the right side of the middle of the main ship body. The first side sheet body and the second side sheet body are provided with water surface and underwater environmental monitoring systems correspondingly. The main ship body is provided with a solar electricity supply system,a fixed time and fixed point water sample collecting and monitoring system, an autonomous oxygen increasing system, a second driving device, a controller and an electricity supply power source. The controller is electrically connected with the electricity supply power source. The electricity supply power source is electrically connected with the solar electricity supply system. The water surfaceand underwater environmental monitoring systems, the fixed time and fixed point water sample collecting and monitoring system, the autonomous oxygen increasing system and the second driving device areelectrically connected with the controller.