This study investigated the effect of the dihydropyridine calcium channel antagonist, amlodipine, on blood pressure (BP) during resistance exercise performed at different intensities in hypertensives. Eleven hypertensives underwent 4 weeks of placebo and amlodipine (random double-blinded crossover design). In each phase, they performed knee extension exercise until exhaustion following three protocols: one set at 100% of 1 RM (repetition maximum), three sets at 80% of 1 RM, and three sets at 40% of 1 RM. Intraarterial BP was measured before and during exercise. Amlodipine reduced maximal systolic/diastolic BP values achieved at all intensities (100% = 225 ± 6/141 ± 3 vs. 207 ± 6/130 ± 6 mmHg; 80% = 289 ± 8/178 ± 5 vs. 273 ± 10/169 ± 6 mmHg; 40% = 289 ± 10/176 ± 8 vs. 271 ± 11/154 ± 6 mmHg). Amlodipine blunted the increase in diastolic BP that occurred during the second and third sets of exercise at 40% of 1RM (+75 ± 6 vs. +61 ± 5 mmHg and +78 ± 7 vs. +64 ± 5 mmHg, respectively). Amlodipine was effective in reducing the absolute values of systolic and diastolic BP during resistance exercise and in preventing the progressive increase in diastolic BP that occurs over sets of low-intensity exercise. These results suggest that systemic vascular resistance is involved in BP increase during resistance exercise, and imply that hypertensives receiving amlodipine are at lower risk of increased BP during resistance exercise than non-medicated patients.