Aiming at the problem of high peak to average power ratio in optical orthogonal frequency division multiplexing (OOFDM) system, the coordinate rotation digital computer(CORDIC) algorithm is used for nonlinear compression, and field programmable gate array(FPGA) is used for hardware implementation. The signal captured from FPGA is analyzed on Matlab, the peak to average power ratio and bit error rate of communication system are calculated, and compared with the traditional OOFDM system. Experimental results show that the algorithm can effectively suppress the peak to average power ratio of the signal and ensure the communication quality.