In this study, we propose a statistical approach based on Taguchi method and Grey relational analysis for effective optimization of indium tin oxide (ITO) films which are used as front contact for shallow emitter based crystalline silicon (c-Si) solar cells. The experiments were designed by the Taguchi method through an orthogonal array, resulting in the reduction of the number of experiments by approximately 90%; the reproduction effect of process parameters on performance characteristics, however, is still ensured. Excellent compromise between electrical and optical properties of ITO films was obtained by Grey relational analysis at power density of 0.685 W/cm(2), working pressure of 0.4 Pa, substrate temperature of 250 degrees C, and post-annealing temperature of 300 degrees C in 30 mm. The ITO films exhibited lowest electrical resistivity of 1.316 x 10(-4) Omega cm, and highest transmittance of 91.251% under optimal condition. The shallow emitter based c-Si solar cells using the optimal ITO films showed highest efficiency of 17.555%, yielding a 1375% absolute increase in efficiency compared to using ITO films with initial condition. Furthermore, using analysis of variance, we found that the substrate temperature was a key parameter which critically affected the opto-electrical properties of ITO films. (C) 2014 Elsevier B.V. All rights reserved.