We report on the high-resolution patterning of III-V semiconductors through polymeric masks by a soft lithographic technique based on micromolding in capillaries. The basic study of the capillarity process and the optimization of the technological steps allowed us to transfer patterns on both GaAs and InP with resolution of 800 nm over areas up to 1 cm(2) and of a few microns over areas up to 4 cm(2).