Plate heat exchanger, heat management system and vehicle

The invention discloses a plate heat exchanger, a heat management system and a vehicle, a heat exchange plate main body comprises a heat exchange plate main body, at least three heat exchange channels which are not communicated with one another are defined in the heat exchange plate main body, and the at least three heat exchange channels comprise a first heat exchange channel, a second heat exchange channel and a third heat exchange channel; the surface of the same side of the heat exchange plate body is provided with a first inlet and a first outlet which communicate with the first heat exchange channel, a second inlet and a second outlet which communicate with the second heat exchange channel, and a third inlet and a third outlet which communicate with the third heat exchange channel. According to the plate heat exchanger, three heat exchange media exist in the plate heat exchanger at the same time, heat exchange of any two or three heat exchange media among the heat exchange media located in the first heat exchange channel, the second heat exchange channel and the third heat exchange channel is achieved, and therefore cost is reduced, installation space is saved, and assembly efficiency is improved. Meanwhile, the three heat exchange media are not mixed, and the heat exchange efficiency of the plate heat exchanger is guaranteed.