This study examined the intricate relationship between supplier trust, retailer trustworthiness, social categorization, and cooperation duration, particularly focusing on their effects on cooperation. Trust and trustworthiness, recognized as pivotal in influencing organizational performance, are analyzed in the context of a supply chain business cooperation. The research underscored how higher levels of trust and trustworthiness enhance cooperative behaviors among employees and business partners, consequently elevating efficiency and productivity. Six regions located in different parts of China were targeted, namely Beijing and Jinan in the North, Chongqing in the Southwest, Shanghai, Fuzhou, and Guangzhou in the South. A total of 228 participants attended the simulated two-tier supply chain experiment. This paper identified the regional characteristics on entry strategies to a new market for supply chain cooperation. The findings of this study contributed to a deeper understanding of social categories in shaping trust dynamics for business partnerships and offering valuable insights for enhancing cooperation.