Indium zinc oxide (IZO) thin films were prepared by radio frequency magnetron sputtering at room temperature for the applications of Cu(In,Ga)Se2 (CIGS) solar cells. The effect of the RF power during the deposition process on the structural, optical, and electrical properties of the films was investigated. XRD analysis revealed that all films showed an amorphous phase. The average optical transmittance in the range of 300-1500 nm decreased with increasing deposition power. Hall effect measurements show that the optimal hall mobility of 34.22 cm2/Vs and resistivity of 4.09×10−4 Ω•cm were obtained at the power of 90 W. The optimized IZO film was applied to CIGS solar cells, and an efficiency of 13.81% in CIGS solar cell has been achieved.