The invention relates to a high-sensitive multimode fiber receiving circuit. The high-sensitive multimode fiber receiving circuit is composed of a multimode fiber receiver, a high-speed operation amplifier and a high-speed comparator which are successively connected, wherein the output end of the multimode fiber receiver is connected with a same phase input end of the high-speed operation amplifier through a first-stage stopping condenser and a resistor bleeder circuit; the output end of the multimode fiber receiver is connected with a positive polarity input end of the high-speed comparator through a second-stage stopping condenser and a connecting power supply and the output end of the high-speed comparator is connected with a rear-stage logic circuit; another input end of the high-speed comparator uses middle power level of a working power supply; and when the transmission rate is 20Mbit/s, the optical fiber receiving sensitivity can be up to -30dB, if the speed rate reduces to be 10Mbit/s, and the optical fiber receiving sensitivity can be increased to be -33 dB. The transmission rate or the receiving sensitivity of the general multimode fiber receiving circuit has definite limitation, and when the distance of a send-receive end is relatively far, an error can exist, the general multimode fiber receiving circuit is not suitable for all application occasions.