A horizontal injection and compression molding apparatus has an injection device (3) and a compression molding device, wherein the compression molding device (2) includes: a stationary die plate (12) for holding a stationary die (11), a movable die plate (22) for holding a movable die (21), means (30) for rapidly extending and retracting the movable die plate (22), relative to the stationary die plate (12), means (40) for locking the movable die plate (22) to tie bars (51) at a position where the movable die plate (22) approaches the stationary die plate (12), and means (50) for fastening the dies after the movable die plate (22) is locked to the tie bars (51); and wherein the injection device (3) for feeding a molten plastic material into a mold cavity (90) between the stationary die (11) and the movable die (21) is characterized in that it initiates feeding of the molten plastic material into the mold cavity ( 90) when the stationary die (11) and the movable die (21) are parted from each other by a predetermined distance, with the plastic material being compressed and drawn while the movable die (21) is moved towards the stationary die (11) after a predetermined quantity of the molten plastic material has been fed into the mold cavity (90).