The invention relates to an optical fiber coupled multimode semiconductor photoelectric device. The optical fiber coupled multimode semiconductor photoelectric device comprises a tube shell, a thermoelectric cooler arranged at the bottom of the tube shell, a heat sink transition block arranged on the thermoelectric cooler, and a semiconductor laser unit, a coupled lens assembly, a thermistor and a backlight detector, the four of which are arranged on the heat sink transition block; a through hole is formed on one side of the tube shell; an optical fiber assembly is put through the through center at the center and hermetically connected with the tube shell; the optical fiber assembly comprises a metal tube and an optical fiber; the end portion of the optical fiber is fixed on an optical fiber transition block and arranged directly to face the coupled lens assembly; the semiconductor laser unit, the backlight detector and the thermistor are electrically connected with the external pins of the tube shell. The optical fiber coupled multimode semiconductor photoelectric device is capable of reducing the power consumption and the cost of an amplifier, and also capable of avoiding the risk of heat and other radiation crosstalk or interference effects between semiconductor chips.