Plate heat exchanger

The utility model relates to the technical field of heat exchangers, in particular to a plate heat exchanger which comprises a heat exchanger core body, the heat exchanger core body comprises a plurality of heat exchange sheets which are stacked at intervals, the middle section of the upper surface of each heat exchange sheet is provided with a plurality of fluid channels, and four corners of each heat exchange sheet are respectively provided with a first through hole, a second through hole, a third through hole and a fourth through hole. The first through hole is oval, a plurality of protruding tips are arranged at the two ends of the first through hole, the first through hole and the third through hole are identical in structure and located on the same side, the edge of the second through hole protrudes to form a circle of protruding edge, the protruding edge is oval, a plurality of concave tip grooves are formed in the two ends of the protruding edge, and the second through hole and the fourth through hole