The invention provides a clamp structure used for parallel face milling of a glass mold, and belongs to the technical field of tool clamps used for manufacture of the glass mold. The clamp structure comprises a bottom plate, a base, a first action cylinder, a second action cylinder, and a movable bearing base. The base is fixed on the upward side of the bottom plate, a connection shaft plate connecting base is formed on the upper portion of one end of the base, a fixed bearing base is fixed on the upper portion of the other end of the base, and a glass mold base plate is fixed in the middle of the base. The first action cylinder and the second action cylinder are located on two sides of the base respectively and fixed on the base. The upper portion of the movable bearing base corresponds to the fixed bearing base, the middle of the movable bearing base is connected with the connection shaft plate connecting base, one end of the lower portion of the movable bearing base is connected with the first action cylinder, the other end of the lower portion of the movable bearing base is connected with the second action cylinder, the upper portion of the movable bearing base corresponds to the upper portion of one end of the glass mold base plate in a vacant state, and the fixed bearing base faces one end of the movable bearing base and corresponds to the upper portion of the other end of the glass mold base plate. Milling efficiency is high, industrialization widened production requirements are met, operation intensity of workers is reduced, the parallelism of parallel faces of the glass mold can be guaranteed, and energy-saving effects are ideal.