The utility model relates to a split type photoelectric encoder. The device comprises a circuit board, a rotating shaft, a coded disc, a base and fixing assemblies, the fixing assembly comprises a fixing ring sleeved with the base, a wedge-shaped supporting block and a rotor. the fixing ring can drive the rotor to rotate on the base; the height of the rotor is changed under the support of the wedge-shaped support block on the base; the rotor abuts against the lower surface of the rotating shaft at the highest position. an air gap between the coded disc and the photoelectric conversion chip onthe circuit board is ensured; a rotating shaft of the motor and a rotating shaft of the photoelectric encoder are fixed through the locking device. then the rotor is rotated to the lowest position towork normally; according to the structure, safe, simple and convenient installation on site can be ensured; compared with an integrated encoder, the encoder has the advantages that the size is small,the height is reduced by about 15mm, the encoder is more suitable for the miniaturization requirement of servo equipment, the encoder main body is made of a plastic material, a pair of bearings is omitted, and the product cost is reduced by about 30%.