A mold clamping apparatus of an injection molding machine, which includes a fixed platen to which a fixed-side mold is attached, a mold clamping housing, a plurality of tie bars provided between the fixed platen and the mold clamping housing and a movable platen to which a moving-side mold is attached and which is capable of moving with respect to the fixed platen along the tie bars. The mold clamping apparatus includes heaters for heating the tie bars and sensors for sensing the temperatures of portions heated by the heaters, and the heaters and the sensors are provided to each of the plurality of tie bars. The mold clamping apparatus includes a temperature adjustor, which is connected to the heaters and the sensors and controls the temperatures of the heated portions of the tie bars.