To exploring the thyroid peroxidase antibody (TPOAb) and transforming growth factor-β (TGF-β) levels of pregnant women with hypothyroidism, and to study their influence on the maternal and fetal adverse outcomes. Methods: The clinical data of 92 pregnant women with hypothyroidism from November 2021 to March 2023 were selected in study group retrospectively. And another 46 healthy pregnant women who came to the hospital for prenatal examination during the same period were selected in control group. The levels of TPOAb and TGF-β of the women during 20 gestational weeks were compared between two groups. The risk factors of the maternal and infant adverse outcomes of the pregnant women with hypothyroidism were analyzed. Receiver operating characteristic (ROC) curve was used to analyze the value of the serum TPOAb and TGF-β levels of the pregnant women with hypothyroidism for evaluating the maternal and infant adverse outcomes. Results: The level of TPOAb (394.26±54.65 U/ml) of the women in the study group was significantly higher than that (19.21±9.13 U/ml) of the women in the control group, and the level of TGF-β (268.79±89.65 ng/L) of the women in the study group was significantly lower than that (381.23±98.45 ng/L) of the women in the control group. The total incidence of the maternal and infant adverse outcomes (29.4%) of the women in the study group was significantly higher than that (8.7%) of the women in the control group. In the study group, the serum TPOAb level of the women with the poor maternal and infant outcomes was significantly higher than that of the women with the normal maternal and infant outcomes, but the TGF-β level of the women with the poor maternal and infant outcomes was significantly lower (all P<0.05). Logistic regression analysis showed that the increase of the TPOAb level and the decrease of the TGF-β level of the pregnant women with hypothyroidism were the risk factors of their maternal and infant adverse outcomes (P<0.05). ROC curve analysis showed that serum TPOAb and TGF-β levels of the pregnant women with hypothyroidism had value for predicting the maternal and infant adverse outcomes. The area under the curve of the combined serum TPOAb and TGF-β levels of the pregnant women with hypothyroidism had value for predicting the maternal and infant adverse outcomes was 0.915, and which was significantly higher than that of the serum TPOAb level or the TGF-β level alone (P<0.05). Conclusion: The serum TPOAb level of the pregnant women with hypothyroidism increases and the TGF-β level of them decreases, and both of which are the risk factors of the maternal and infant adverse outcomes. The combination of the serum TPOAb and TGF-β levels of the pregnant women with hypothyroidism has higher clinical value for predicting the maternal and infant adverse outcomes.