The impacts of ownership on enterprise efficiencies have been a key research issue. The current literature presents some controversies about the specific aspects of such impacts. Additionally，there is a lack of empirical analysis that comprehensively considers and compares the impact of various aspects under the same framework. This article proposes a dual-distortion framework and then calculates the efficiencies of China’s central state-owned enterprises （SOEs） and big private businesses from 2003 to 2013. It also uses a RE and GMM model to further test the hypothesis. The results indicate that under the traditional economic-oriented output model，state ownership has a negative on the efficiency of large companies. However，when the dual distortions are taken into consideration，state ownership begins to have a positive influence. This research reveals the direction of the effect of ownership on large firms under different output models. It provides policy recommendations and helpful ideas regarding further reforms of the central SOEs.