An objective sound quality evaluation method for headphones is proposed which simulates the subjective listening evaluation. Considering the characteristics of the headphone which is different from the loudspeaker case, objective factors that play a key role in sound quality of the headphone are carefully selected. These factors are mathematically modeled, transformed and converted to the index that could represent the overall sound quality of headphones. The comparative analysis between the proposed objective test and subjective listening test showed the effectiveness of the method presented in this paper.