Abstract: Background and Objective: Adenomyosis is a disease characterized with heterotrophic stromal and endometrial glands within myometrium surrounded by myometrium hyperplasia. Alterations of immunological system contributed in adenomyosis pathogenesis. One of the cytokines role in adenomyosis pathophysiology is IL-10. This research aimed to investigate the comparison of IL-10 in women with adenomyosis and without adenomyosis. Materials and Methods: The research was conducted at Wahidin Sudirohusodo General Hospital and at the network hospitals using the nested case control method. The samples were 37 women with adenomyosis and diagnosed based on the histopathology results and 37 women without adenomyosis. The levels of IL-10 were measured using ELISA method. The data were analyzed using Chi-square test, Mann-Whitney test and Spearman correlation test with the significance of p = 0.05. Results: The finding of this study indicated that the levels of IL-10 in women with adenomyosis were higher compared to the women without adenomyosis (p = 0.001). IL-10 levels has a weak correlation with the incidence of adenomyosis and medium correlation with the size of adenomyosis. Conclusion: So it was concluded that there was increased levels of IL-10 in adenomyosis patients compared with no adenomyosis.