Abstract: Objective This study aimed to analyze the impact of the specialized centralized volume-based procurement policy for insulin (hereinafter referred to as "centralized procurement") on insulin utilization, and to provide data support for better advancing centralized volume-based procurement initiatives as well as the formulation and improvement of relevant policies. Methods The indicators of changes in insulin unit price, utilization volume, sales amount, defined daily dose system (DDDs), defined daily dose cost (DDDc), and individual patients, economic burden were compared between the same periods before (May 30, 2021 to May 29, 2022) and after (May 30, 2022 to May 29, 2023) the implementation of the specialized centralized volume-based procurement policy for insulin. Results After the implementation of centralized procurement, the number of insulin specifications increased by 5; the average unit price decreased by 50.56%; the total utilization volume increased by 11.33%; and the total sales amount dropped by 48.54%. Additionally, the actual cost savings from insulin reached over RMB 3.51 million, with an average annual insulin cost saving of RMB 958.24 per patient. Conclusion The specialized centralized volume-based procurement policy for insulin can significantly reduce insulin prices, effectively alleviate patients, economic burden, and promote the rational use of insulin among patients. However, more data regarding insulin utilization patterns and patients, medication adherence deserves further collection and analysis to facilitate the implementation and improvement of the policy.