The work aims to study the effect of process parameters on the electrochemical machining speed and processing quality of TC4 titanium alloy. The influence laws of frequency, duty and machining gap on machining speed and machining quality were studied by orthogonal experiment with three factors and three levels. The F test was carried out on the orthogonal test results and the significance of the processing parameters was analyzed. The surface morphology and the surface roughness of the workpiece were characterized and measured by laser confocal microscope. The numerical simulation model of the flow field in the electrolyte was established to obtain the flow laws of the electrolyte during the process of electrolysis. The effect of electrochemical machining frequency and machining gap on the removal of ECM material was significant. The effect of duty ratio on material removal was not significant. The material removal was the largest, the surface roughness is the lowest, the material removal amount reached 0.261 g and the surface roughness of the workpiece reached 0.484 μm under the processing gap of 0.2 mm and the processing frequency of 100 Hz. The reduction of the machining gap or the increase of the machining frequency was beneficial to the improvement of the material removal and the reduction of the surface roughness of the workpiece. The distribution of electrolyte flow velocity in the ECM area wasin good agreement with the processing depth of the electrolytic processing area. The frequency and gap of ECM have a great influence on the machining speed of ECM and the machining quality of ECM. In the actual processing, the machining gap rate should be reducedand the machining rate should be improved to increase the machining speed and machining quality. The uniformity of the velocity distribution of the electrolyte in the processing area has a certain influence on the uniformity of the workpiece surface. A fixture should be designed to improve the uniformity of the flow velocity in the processing area in order to improve the uniformity of the processing surface.