The venoarteriolar reflex (VAR) is one of the several physiological responses that contribute to maintain hemodynamic stability, especially in dependent regions of the body. VAR consists on arteriolar constriction in response to an increase in venous transmural pressure, as occurring in postural changes, therefore preventing the formation of edema. A recent study has demonstrated, in the lower limb, the existence of a vascular response in the contralateral limb that occurs simultaneously to VAR. However, it remains unclear whether this contralateral response is also observed in the upper limb. This study aimed to quantify the microvascular changes to a postural modification designed to evoke VAR in the upper limb. Ten young healthy subjects (23.4 ± 4.9 y.o.; 6 females, 4 males) participated in this study after giving informed consent. After acclimatization, subjects performed a postural modification while sitting upright, as follows – 7 min with both hands at heart level (baseline phase), 5 min with one random hand (test) placed 40 cm below the heart (challenge phase), and 7 min in the initial position (recovery phase). Local blood flow and skin temperature were measured in the second finger of both hands. Galvanic skin response was measured in the third and fourth fingers of the unmoved (control) hand in order to assess sympathetic cutaneous activity. These variables were compared between the different phases of the protocol with the Wilcoxon signed rank test (p<0.05). During the challenge phase a significant decrease in local blood flow was observed for the test hand. Similarly, there was a decrease in blood flow in the control hand, although not statistically significant. Skin temperature did not show any statistical differences between phases, guaranteeing that blood flow changes were not related to thermoregulatory phenomena. Also, no significant changes were found for galvanic skin response, suggesting that the sympathetic nervous activity is not involved in the observed vascular responses. These results suggest that the contralateral vasoconstrictor response to VAR, previously demonstrated in the lower limb, is also detected in the upper limb. The specific nature of this contralateral response should be investigated in future studies.