Cubic Cu(1.4)S nanoparticles were synthesized on a large scale by laser ablation of salt powder dispersed in an organic solvent. A metastable Cu(1.4)S phase was formed at high temperature in a reductive solvent and was maintained at room temperature due to the quenching effect of the pulsed laser. The cubic Cu(1.4)S nanoparticles show good stability after being exposed to ambient atmosphere for as long as 1 month.