Device for injecting a liquid from a syringe (1) comprises a piston, an actuating device (5) removably connected to the end of the piston protruding from the syringe in a piston recess (50), and a holder (3) for the syringe. The piston recess of the actuating device and the holder for the syringe are fixed on a support part (4). The holder for the syringe can be heated. Preferred Features: The holder is made of a heat-conducting material and is provided with a heating device.