A 650 nm monolithic optical receiver for plastic optical fiber communication is proposed, including a photodetector, a tranimpedance preamplifier, a single to differential conversion, a cascade of differential amplifiers, an output buffer and an offset voltage compensation. Based on reasonable assumption and approximation, the spectral response of photodetector is analyzed according to its steady-state continuity equation and boundary conditions. Analysis of frequency response is established due to the basic equations of the photodetector by Laplace transform method. The layout area of monolithic optical receiver is about 832×948 μm2 with 0.5 μm BCD process. Measurement results indicate that the responsivity of photodetector is 0.26 A/W for 650 nm at 5 V reverse bias. The sensitivity is -14.6 dBm at 180 Mbps and bit error rate less than 10-9. A clear eye diagram is demonstrated for 100Mbps pseudorandom binary sequence and bit error rate less than 10-9.