With the method of metal-catalytic chemical etching (MCCE), when employing metal Ag as catalyst, zigzag silicon nanowire arrays were fabricated by conducting alternate etching experiments on P(111) silicon substrate in HF and H₂O₂ systems. Scanning electron microscope (SEM) was adopted to characterize the morphology of silicon nanowires. The mutual effect of HF and H₂O₂ solution’s concentration on the etching direction of silicon nanowires was investigated, and isotropic etching and anisotropic etching were intensified through respectively adjusting and controlling the concentration of HF and H₂O₂ solution, making it possible that the etching direction can make rapid response to the solution concentration during the alternate etching process. Zigzag silicon nanowires with highly adjustable etching direction were fabricated when conducting alternate etching experiments in solution Ⅰ([HF]=2.3 mol/L,[H₂O₂]=0.4 mol/L) and solution Ⅱ([HF]=9.2 mol/L,[H₂O₂]=0.04 mol/L). The anti-reflection properties of zigzag silicon nanowires were measured by UV-Vis spectrophotometer, the lowest reflectivity was 5.9%, which shows a good prospect for photovoltaic applications. Because of the high controllability of the nanowires morphology, it has a great application prospect in the field of microelectronic devices.