Open innovation provides a new perspective and method for enterprises and other innovative entities to develop technology. However, studies on effectiveness of open innovation remain need to be deepened. This paper takes maintaining of patents as a proxy variable for patent quality, uses virtual regression method to analyze the impact of two factors on patent quality. One is the participation of universities and research institutions, while another is the adopting of open innovation. Regression analysis showed that the participation of universities and research institutions can not improve patent quality, while the joint development based on open innovation can significantly improve the quality of patents. Finally, this paper renders some suggestions to promote effect of open innovation and patent quality.