Objective To study and compare the cathodic protection effect of pulse current and DC current. Methods The plate hanging method was used to contrast the cathodic protection effect of pulse current and DC current on Q235 steel in NaCl solution when the power output voltage was 4. 02 V (DC cathodic protection potential was 0. 95 V). Results Under the same power output condition, pulse current had better protection effect and lower power consumption. As time went on, under different pulse current parameter conditions, the cathodic protection potential became more and more negative. Conclusion Under the terms of high frequency, pulse current had better protection effect than DC current. To simultaneously improve the protection effect and decrease the power consumption, middle range of duty ratio, high frequency and priority adjustment of frequency should be adopted.