The invention discloses a clamping and turnover mechanism for optical glass. The clamping and turnover mechanism comprises a rack, wherein side support plates are fixed on two sides of the rack and located on two sides of the optical glass, rotating shafts are fixed at the outer side ends of cylindrical casings and hinged to the side support plates, rotating gear rings are fixed on the outer side walls of the cylindrical casings, driving motors are fixed on the top surface of the rack, and driving gears are fixed on output shafts of the driving motors and meshed with the rotating gear rings; middle connecting plates are fixed in the cylindrical casings, telescopic motors are fixed on inner side walls of the middle connecting plates, rotating shafts of the telescopic motors penetrate through the middle connecting plates and are in screw joint with telescopic screws, clamping movement blocks are fixed at ends of the telescopic screws, clamping blocks are fixed at opposite ends of the two clamping movement blocks, and clamping grooves are formed in opposite wall surfaces of the two clamping blocks. The clamping and turnover mechanism can automatically clamp and turn over the optical glass and is high in automation degree, good in effect and high in efficiency.