Abstract: The AC voltage distortion caused by the failure of the AC system at the receiving end of the DC transmission is one of important reasons for the DC commutation failure. At present, the research on commutation failure caused by harmonics mostly focuses on the second and third harmonics, but more high-order harmonic components will also emerge after the commutation voltage is distorted, which will also affect the commutation process. Based on the commutation voltage-time area theory, this paper analyzes the principle of commutation under the influence of multiple voltage harmonic components after the commutation voltage distortion, through the ratio of critical supply-demand commutation area (RCSD), it is found that the multiple harmonic components of the commutation voltage will have an adverse effect on the commutation at the beginning of the AC fault, At the same time, the mathematical expression of the commutation voltage zero-crossing point offset is derived by using the phasor diagram of the AC voltage after the fault, then this paper designed a commutation failure suppression strategy considering multiple voltage harmonics. Finally, the proposed strategy is compared with the strategy that only considers 2nd and 3rd harmonics and the commutation failure prevention(CFPREV) control strategy. The results show that the control strategy considering multiple harmonics can effectively improve the system's resistance to commutation failure.