A high sucrose diet during pregnancy may generate profound effects on vascular diseases in offspring later in life. Pulmonary artery (PA) functions is closely related to pulmonary hypertension, but whether and how prenatal high-sucrose diet (HS) affect pulmonary vasoreactivity in adult offspring remains unknown. We investigated the alterations of PA reactivity in postnatal offspring exposed to prenatal HS. Pregnant Sprague-Dawley rats were fed either a tap water or 20 % high sucrose solution throughout pregnancy. Pulmonary arteries from adult offspring were isolated and tested for all experiments. Prenatal HS increased vascular wall thickness, resulted in swollen mitochondria, and altered myofilament distribution in vascular smooth muscle layers of PA. Notably, the offspring's PAs from HS group showed increased vasoconstriction, but reduced PKC function and expression, suggesting that the dysfunction was not primary linked to PKC signals. RNA-Seq analysis of PA revealed that the MT1R and MT2AR genes were significantly increased in the HS group, but their protein levels decreased. This suggests that MT receptors, rather than PKC signaling, are the key factors to influencing vascular contraction of PAs exposure to prenatal HS.