We demonstrate the fabrication of ZnSe nanoparticles using fs laser pulses. Following the irradiation of fs laser pulses at a wavelength of 800 nm and pulse duration of 100 fs, many hexagonal-phase ZnSe nanoparticles formed on the surface of an undoped (100) cubic ZnSe single-crystal wafer. The interesting phase transition from the cubic structure of ZnSe single-crystal wafer to the hexagonal structure of ZnSe nanoparticles may have been caused by the ultra-high ablation pressure at the local area due to the sudden injection of high-energy leading to solid-solid transition.