The influence of quality management practices on quality performance and firm performance is analyzed based on the literature review. Supply chain relationship quality is introduced as a regulative variable to discuss its regulative effect on the relationship between quality management practices and quality performance and firm performance. A conceptual model incorporating quality management practices, quality performance, and firm performance is examined by using the data collected from firms in Shaanxi, Ningxia, Gansu, Xinjiang, and Zhejiang Provinces. The results indicate that quality management practices have an indirect positive impact on firm performance with the regulative effect of internal and external quality performance. Moreover, supply chain relationship quality moderates the relationship between quality management practices and internal quality performance.