Previous studies have demonstrated that young men exhibit greater blood pressure responses to exercise compared to young women. The neural mechanism(s) involved in such augmented responses in men remain unclear; however, sex differences in arterial baroreflex regulation of blood pressure may be involved. Indeed, the arterial baroreflex is of fundamental importance for evoking and maintaining the normal cardiovascular adjustments to exercise via modulating autonomic nervous system activity to the heart and vasculature. In particular, a properly functioning arterial baroreflex is critical to regulate blood pressure during exercise in which it protects against excessive sympatho-excitation and hypertension. Presently, animal and human studies have reported inconsistent findings on arterial baroreflex control when comparing sexes. Furthermore, whether sex influences arterial baroreflex control of blood pressure during dynamic exercise has not been investigated. A unique aspect in women that requires consideration when comparing responses to men is the potential impact of fluctuations in ovarian hormones. Although estrogen has been suggested to contribute to sex-related differences, a systematic examination of the influence of estrogen and progesterone on arterial baroreflex function and exercise-induced pressor responses has not been performed in humans. As such, we will present preliminary data examining sex differences in carotid baroreflex control at rest and during exercise. Five second pulses of neck suction and neck pressure were applied to load (carotid hypertension) and unload (carotid hypotension) the carotid baroreflex, respectively at rest and during steady-state cycling at 50% heart rate reserve. In comparison to men, young women appear to be better able to defend against hypertensive challenges at rest, whereas during exercise women appear to more effectively buffer against hypotensive stimuli. Furthermore, increases in endogenous estrogen and progesterone appear to selectively augment carotid baroreflex-mediated blood pressure responses to hypotension without effect on carotid baroreflex responses to hypertension. Interestingly, carotid baroreflex control of heart rate was not affected by changes in estrogen and progesterone throughout the menstrual cycle either at rest or during exercise. Overall, these preliminary findings suggest clear sex differences in arterial baroreflex control of blood pressure both at rest and during exercise.