Abstract Context Previous studies suggested a potential link of maternal thyroid dysfunction with adverse neurocognitive outcomes and impaired development of internal organs in offspring. Objective To review the association between maternal thyroid dysfunction and the risk of adverse outcomes in offspring. Data Sources PubMed, EMBASE, and Cochrane Library. Study Selections Eligible studies reported the association between maternal thyroid hormone function and the risk of adverse outcomes in their children. Data Extraction Reviewers extracted data on study characteristics and results independently. Data Synthesis Estimates were pooled and reported as odds ratio (OR) with 95% confidence interval (CI). I2 tests were applied to assess the heterogeneity across studies. Results We identified 29 eligible articles and found an association between maternal hyperthyroidism and attention deficit hyperactivity disorder (ADHD) (OR: 1.18, 95% CI: 1.04-1.34, I2 = 0%) and epilepsy (OR: 1.19, 95% CI: 1.08-1.31, I2 = 0%) in offspring; as well as an association of maternal hypothyroidism with increased risk of ADHD (OR: 1.14, 95% CI: 1.03-1.26, I2 = 25%), autism spectrum disorder (OR: 1.41, 95% CI: 1.05-1.90, I2 = 63%), and epilepsy (OR: 1.21, 95% CI: 1.06-1.39, I2 = 0%) in offspring. Conclusion Routine measurement and timely treatment on thyroid function should be considered for pregnant women.