Aiming at the problem of high peak to average power ratio of asymmetrically clipped optical orthogonal frequency division multiplexing system applied in visible light communication,a joint scheme combining Hadamard precoding with normalized μ law companding is proposed to reduce peak to average power ratio on the basis of the study of coding technology and distortion technology.The simulation results of the joint scheme demonstrate an improvement of 5.8 dB in peak to average power ratio suppression performance compared to Hadamard precoding alone.Additionally,compared to normalized μ law companding,it still exhibits superior performance in terms of error rate,achieving a 2 dB optimization.