Altered renal sympathetic nerve activity (RSNA) plays a major role in the progression of cardiac hypertrophy. We aimed to evaluate the baroreflex control of RSNA in mice with cardiac hypertrophy. Swiss Webster mice were treated with isoproterenol (15 μg/g/day, s.c.) or vehicle and the baroreflex evaluation was performed by measuring changes in RSNA in response to changes in arterial pressure. The maximal gain of the reflex changes in RSNA was reduced in isoproterenol-treated animals (1.39 ± 0.08%/mm Hg) in comparison with vehicle-treated animals (1.77 ± 0.10%/mm Hg). Therefore, we can conclude that cardiac hypertrophy led to a reduced sensitivity of baroreflex control of RSNA.