Abstract: Enhancing NPD efficiency through cross-functional integrations is the key to new product development management. However, empirical studies in this subject are scarce. This study investigates the effects of five different cross-functional integrations on NPD efficiency from knowledge acquisition perspective. It also explores the impact of knowledge acquisition on NPD efficiency. Finally, we found the relationships between five different cross-functional integrations and NPD efficiency are not same and we clarified the mechanisms that cross-functional integrations have significant effects on NPD efficiency through knowledge acquisition. These results can provide implications for the NPD management practices.