The participation of foreign-invested enterprises in the formulation of national standards is taken as an opportunity to identify standards opening-up, and the impact of standards opening-up on local firms' innovation is examined. It is found that standards opening-up promotes local firms' innovation, works through collaboration between Chinese and foreign firms, market competition, and information transmission mechanism, and influences upstream and downstream innovation along the industrial chain. In addition, standards opening-up promotes firms’ product upgrading and exporting, standards harmonization, and foreign investment stabilization. These findings explain the significance of steady expansion of institutional opening-up.