It has been reported that people with asthma have an increased risk of hypertension. However, little is known about the specific relationship between asthma and hypertension in young adults. Among subjects who participated in the Korea National Health and Nutrition Examination Survey conducted in 2008-2013, a total of 10,138 young adults (4,226 men and 5,912 women) aged 19-39 years were analyzed. Multiple logistic regression analysis was used to estimate adjusted odds ratios (ORs) and 95% confidence intervals (CIs). The prevalence of ever asthma was 11.1% in men and 8.4% in women. The mean diastolic blood pressure (DBP) was lower in men with asthma than in men without asthma (p = 0.03), whereas the mean DBP was higher in women with asthma than in women without asthma (p = 0.04). Having asthma was inversely associated with hypertension in men (OR: 0.62, 95% CI: 0.41-0.91). In contrast, having asthma was positively associated with hypertension in women (OR: 2.19, 95% CI: 1.19-4.02). Our results suggest that asthma pathophysiology might be differentially associated with hypertension in young adults depending on sex.