Abstract: Taking 42CrMo as an example, the effects of electrochemical etching with different electrical parameters on the surface texture of the alloy steel were studied. DC voltages with different voltage values,14V non-negative pulses and 14V positive and negative pulses with different frequencies and duty ratios were used to electrochemically etch 42CrMo alloy steel.Surface data was collected on the processed surface using a surface profilometer, and the surface topography was calculated using numerical analysis methods. The results show that the etching voltage is too low, resulting in too small etching rate, high etching voltage, resulting in poor etching surface quality. The overall effect of etching is better when the voltage is 14V. Under the condition of positive pulse etching, the etching system itself has the influence of natural frequency. The test uses PWM etching with a frequency of 20 kHz and a duty cycle of 50% to obtain a surface with relatively low surface roughness. When the frequency is 1 kHz and the duty cycle is 5%, the obtained surface roughness is the highest, and its surface can be used to increase the friction; under the condition of positive and negative pulse etching, the effect of negative pulse plating at low duty cycle offsets the effect of positive pulse etching, resulting in a slow etching rate, but its surface roughness is low, when the frequency is 20 kHz and the duty cycle is 50%, the surface roughness is lowest, and the surface can be used for electrochemical finishing.