Abstract: China and Japan are important trading partners to each other. The structure of trade products of the two sides is highly concentrated, the market is highly interdependent, and trade competitiveness and complementarity coexist. The Regional Comprehensive Economic Partnership (RCEP) will have a great impact on ChinaJapan trade in goods through the trade creation effect, trade diversion and trade reversal effect of ChinaJapan mutual tariff concessions, the lowering effect of the preferential threshold of the cumulative rules of origin, the costreducing effect of customs procedures and trade facilitation, and the indirect exportdriven effect of trade in services and investment agreements. The simulation evaluation results of the GTAP model show that the tariff reduction between China and Japan will promote the import and export scale of both countries and have a stronger effect on Japan, improve their GDP and social welfare but deteriorate Chinas term of trade and and trade balance. The bilateral import and export volume in all industries between China and Japan will increase, but the industry heterogeneity is obvious, of which the textile will have the largest increase in exports to Japan，and mechanical and electrical products have the largest increase in imports from Japan. Chinas goods trade deficit with Japan will increase. Therefore, China should formulate flexible policies to respond to industrial shocks, make full use of the Cumulative Rules of Origin, pay attention to the promotion of preferential arrangements for nontariff barriers, and do a good job in preventing trade risks.

Key words: RCEP, tariff concessions, China-Japan trade in goods, GTAP model