Multi-finger PIN photodetector was designed and optimized in a standard 0.25 μm BCD (Bipolar,CMOS and DMOS) process.The optimized large-area multi-finger structure PIN photodetector was applied in the monolithic optoelectronic receiver with a trans-impedance amplifier and a pre-amplifier.Based on simulation and test results,it is shown that 650nm responsibility of PIN photodetector is improved up to 0.260 A/W and the junction capacitance is decreased down to 4.39pF for the multi-finger structure.The receiver achieves a sensitivity of -23.3 dBm with the bit-error-rate of 10-9 at 250 Mb/s at 650 nm.A clear eye diagram of the proposed receiver is demonstrated for 250 Mb/s.Results indicate that the monolithic optical receiver can be applied to 250 Mb/s plastic optical fiber communication.