Endocrine therapy combined with ovarian function suppression (OFS) is recommended in intermediate- or high-risk patients among premenopausal women with hormone receptor-positive early breast cancer. However, in China, the cost-effectiveness of this strategy compared with endocrine therapy alone is unclear. This study aimed to evaluate the long-term cost-effectiveness of tamoxifen (TAM), TAM+OFS, and exemestane plus OFS (EXE+OFS).On the basis of prognostic data from the Suppression of Ovarian Function Trial (SOFT), cost data from the Hospital Information System of the West China Hospital of Sichuan University, and health utility values from the published literature, a Markov model was established. The incremental cost-effectiveness ratio (ICER) was used to compare the treatment strategies.In a 25-year simulation of adjuvant therapy in Chinese women with early breast cancer, the total costs of TAM, TAM+OFS, and EXE+OFS were $7821, $9318, and $9445, respectively. The quality-adjusted life-years (QALYs) were 11.615, 11.896, and 11.734 years, respectively. Compared with TAM, the ICERs of TAM+OFS and EXE+OFS were $5,327.4021/QALY and $13,647.0588/QALY, respectively. The ICERs of TAM+OFS and EXE+OFS were below the threshold of $32,517/QALY. The reliability and stability of the simulation results were verified using Monte Carlo simulation and sensitivity analysis.In the context of limited resources in China, TAM+OFS and EXE+OFS are cost-effective options compared with TAM.Copyright © 2023 The Authors. Published by Elsevier Inc. All rights reserved.