An injection device has a cylinder member having a supply opening (215) formed in a predetermined position of the member; an injection member provided so as to be advanceable and retreatable in the cylinder; a molding material supply device installed at the supply opening (215) and supplying a molding material into the cylinder through the supply opening (215); and thermal electric cooling elements (261-264) arranged at predetermined positions around the supply opening (215). Since the thermal electric cooling elements (261-264) are arranged at the predetermined positions around the supply opening (215), the temperature around the supply opening (215) can be set to an appropriate level and temperature control response can be improved. Further, when a thermal electric cooling element (g) is disposed between a housing (152) of a drive section and a heat transfer member, heat in the housing (152) is transmitted to the heat transfer member through the housing (152) and emitted to outside the drive member. Accordingly, rated torque produced by driving the drive section can be increased.