To obtain an injection molding apparatus which can accurately and surely keep an optimum molding condition with a mold and can accurately and rapidly input the molding condition.

The injection molding apparatus is provided with a mold 20 for molding which has a movable mold 22 and a fixed mold 21 and has a cavity 29 formed between the movable mold and the fixed mold, a movable platen 18 on which the movable mold 22 is mounted, a fixed platen 17 on which the fixed mold 21 is mounted, an injection cylinder 12 provided on the fixed platen 17 side and for injecting a molten resin into a cavity 29 and a controller for controlling injection of the molten resin based on the molding condition. The mold 20 for molding is provided an RFID tag 31 in which the molding condition is stored. A reader-writer 36 capable of reading the molding condition from the RFID tag 31 and outputting the read molding condition to the controller is provided. The controller is constituted in such a way that injection of the molten resin is controlled based on the output of the reader-writer 36.