Hypertensive disorders of pregnancy (HDP) as a group of medical complications in pregnancy are believed to be associated with an increased risk of poor fetal growth, but the influence on offspring's body composition is not clear. The aim of the present study was to evaluate the association between maternal HDP and overweight status in the offspring of mothers with gestational diabetes mellitus (GDM). A cross-sectional study among 1263 GDM mother-child pairs was performed in Tianjin, China. General linear models and logistic regression models were used to assess the associations of maternal hypertension in pregnancy with anthropometry and overweight status in the offspring from birth to 1–5 years old. Offspring of GDM mothers who were diagnosed with hypertensive disorders during pregnancy had higher mean values of Z-scores for birth weight for gestational age and birth weight for length, and higher mean values of Z-scores for weight for age, weight for length/height, and body mass index for age at 1–5 years old than those of GDM mothers with normal blood pressure during pregnancy. Maternal HDP were associated with increased risks of large for gestational age (OR 1.74, 95% CI 1.08–2.79) and macrosomia (OR 2.02, 95% CI 1.23–3.31) at birth and childhood overweight/obesity at 1–5 years old age (OR 1.88, 95% CI 1.16–3.04). For offspring of mothers with GDM, maternal hypertension during pregnancy was a risk factor for macrosomia at birth and childhood overweight and obesity, and controlling the maternal hypertension may be more important for preventing large-for-gestational-age babies and childhood obesity.