In order to solve the problem of peak to average power ratio (PAPR) in DC-biased optical orthogonal frequency division multiplexing (DCO-OFDM) visible light communication (VLC) system,a joint PAPR reduction algorithm based on combining clipping and normalized μ-law companding is proposed.Firstly,some big peak signal in the time-domain is clipped by amplitude limiting to reduce the amplitude of the signal,and then the clipped signal is further processed by a normalized μ-law companding transform.With this way,the PAPR of DCO-OFDM signal can be effectively reduced.Experimental simulation result shows that the value of complementary accumulative function is １０－３ when 16QAM modulation is adopted,compared with the algorithm combined amplitude limiting with traditional μ-law companding transform,the PAPR of the combined algorithm decreases by about 2.206 dB.