Laser‐induced anisotropic chemical etching of silicon is reported, by using a 488 nm Ar+laser in direct write mode and high‐pressure Cl2process gas. Surface modifications directly comparable with conventional anisotropic wet etching methods have been obtained. A main role in the process is played by the masking effect due to a thin uniform SiO2film grown on the Si substrate. An explanation of the etching mechanism is attempted.