The invention provides a fabrication method for a chalcopyrite powder. The fabrication method includes: (a) mixing a Group IB compound and a Group IIIA compound in a solvent; (b) drying or precipitating the solution of step (a) to obtain a precursor containing Group IB and Group IIIA elements; (c) mixing a solution or powder containing a Group VIA compound with the precursor; and (d) heating the mixture of step (c) to obtain the chalcopyrite powder.