Recovery method of silicon wafer from defective products generated from manufacturing process of silicon solar cells was studied. The removal effect of the N layer and antireflection coating(ARC) of the waste solar cell were investigated at room temperature (25 oC) by variation of concentration of H3PO4, NH4HF2, and concentration and types of chelating agent. Removal efficiency was the best in the conditions; 10 wt% H3PO4 2.0 wt% NH4HF2, 1.5 wt% Hydantoin. Increasing the concentration of H3PO4, the surface contamination degree was increased and the thickness of the silicon wafe became thicker than the thickness before surface treatment because of re-adsorption on the silicon wafer surface by electrostatic attraction of the fine particles changed to (+). The etching method by mixed solution of H3PO4-NH4HF2-chelating agents was expected to be great as an alternative to conventional RCA cleaning methods and as the recycle method of waste solar cells, because all processes are performed at room temperature, the process is simple, and less wastewater, the removal efficiency of the surface of the solar cell was excellent.