In a thermostatic valve for connecting an automatic transmission with an oil cooler, wherein the connection between an inlet conduit 12 for oil coming from the transmission and an outlet conduit 13 to the oil cooler is released or blocked by valve slider element 22, which is actuated by a thermostatic actuating element 16, 17 and is spring-loaded by a restoring spring 21, the valve slider element 22 with the restoring spring 21 is designed as a pressure-control valve which, with the open connection between the inlet conduit 12 for oil coming from the transmission and the outlet conduit 13 to the oil cooler, opens a bypass conduit 24 when a predetermined pressure of the oil is exceeded.