Disclosed is a separating device (1) for cutting profiled plastic elements, comprising a work bench (2) across which the profiled plastic element is guided. A metallic cutting knife (5) is driven relative to the work bench (2). A heating apparatus (14) that encompasses a power source (18) is used for heating the cutting knife (5). The heating apparatus (14) is equipped with a heating induction coil (15) that is spaced apart from the cutting knife (5). The power source (18) is provided with an electrical supply unit for feeding a voltage to the induction coil (15). A separating device (1) which does not necessarily comprise a metallic cutting knife (5) and does not necessarily encompass a heating induction coil for heating is fitted with a temperature sensor (27) for detecting the temperature of the cutting knife (5). The respective separating device has an improved cutting performance.