Overweight compared to normal weight individuals typically possess reduced limb blood flow at rest and during mental challenge. The effect of a single bout of aerobic exercise on cardiovascular reactivity of young overweight males, however, is undetermined. Thus, the purpose was to examine the cardiovascular reactivity response of overweight males to mental challenge before and after acute aerobic exercise. Fifteen normal weight (NW) males with body mass index (BMI) between 18 and 25 kg/m 2 and 15 overweight males (OW) with BMI > 25 kg/m 2 aged 18-30 years acted as participants. All males underwent a 5-min Stroop task before and after one single 30-min bout of cycle exercise at 65% of maximal oxygen uptake (V O 2max). Heart rate, blood pressure, arterial stiffness, and forearm blood flow (FBF) were assessed during Stroop task before and after acute exercise. Arterial stiffness of the OW was significantly higher than NW during Stroop before (p =0.01) and after exercise (p = 0.001). After exercise, the OW had significantly smaller increase in FBF throughout Stroop (p = 0.04) compared to NW. The smaller increase in FBF throughout the Stroop in the OW was also accompanied by higher Stroop errors compared to that of NW (p = 0.01). Stroop errors were positively correlated with BMI, waist circumference, waist/hip ratio, and body fat percentage, whereas post-exercise FBF was positively correlated with V O 2max (p < 0.05). Being overweight was associated with a blunted FBF reactivity response and a greater number of errors during the Stroop task.