To investigate the correlation between the Th1 and Th2-related cytokines levels of pregnant women with subclinical hypothyroidism(SCH) and their adverse pregnancy outcomes. Methods: The clinical data of 70 pregnant women with SCH admitted to the hospital from January 2021 to May 2023 were collected retrospectively. All these women were divided into group A(42 women with normal pregnancy outcomes) and group B(28 women with adverse pregnancy outcomes) according to their pregnancy outcomes. The basic information of the women in the two groups was analyzed. The levels of  Th1-related cytokines, such as interleukin(IL)-2, tumor necrosis factor-α(TNF-α), γ-interferon(IFN-γ), and Th2-related cytokines, such as IL-4, IL-10 and IL-6, of the women were compared between the two groups. Point-biserial correlation analysis and multiple logistic regression analysis were conducted to analyze the correlation between the Th1 and Th2-related cytokines levels of the women with SCH and their adverse pregnancy outcomes. Results: The levels of serum IL-2, TNF-α, IFN-γ and IL-6 of the women in group B were significantly higher than those of the women in group A, and the levels of serum IL-4 and IL-10 of the women in group B were significantly lower than those of the women in group A(P<0.05). Point-biserial correlation analysis showed that the levels of IL-2, IFN-γ, TNF-α and IL-6 of the women with SCH were positively correlated with their adverse pregnancy outcomes, and the levels of IL-10 and IL-4 of the women with SCH were negatively correlated with their adverse pregnancy outcomes(all P<0.001). Logistic regression analysis showed that the increased levels of serum IL-2 and TNF-α, IFN-γ, IL-6 and thyroid-stimulating hormone, and the decreased levels of IL-4 and IL-10 of the pregnant women with SCH were all the risk factors of their adverse pregnancy outcomes. Conclusion: The levels of IL-2, TNF-α, IFN-γ and IL-6 of the pregnant women with SCH are increased, while the levels of IL-4 and IL-10 are decreased, and all of which are correlated with the adverse pregnancy outcomes of the women.