The utility model discloses a plate type exchanger mainly comprising heat transfer sheets 1 which are formed by compressed stainless steel or titanium alloy, sealing cushions 2, clamping bolts, pressing plates 3, an integrated machine framework and other parts, wherein herringbone ripples are arranged on the heat transfer sheets 1, and mediums flow to form turbulence, thereby higher heat transfer efficiency is obtained; the clamping plates 3 are positioned at two sides of a heat transfer sheet group, sealing cushions 2 are arranged at a water inlet pipe 4 and a water outlet pipe 5 of the heat transfer sheets 1, and a signal hole is arranged on each sealing cushion 2 and is capable of discovering and eliminating the leakage in time, thereby not only capable of warming safely, but also avoiding that the two mediums are mixed. The heat transfer sheets 1 are all of independent elements and can increase and decrease the heat space and the flow path freely according to requirements; and as the plate type exchanger adopts the structure, the temperature is reduced rapidly, the defect that the heat exchange is slow is solved, and the aim of highly-efficient heat exchange is achieved.