The hypothesis that reduced cardiac filling, as a result of lower body negative pressure and post-exercise hypotension, would attenuate the reflex changes to heart rate (HR), skin blood flow (SkBF) and mean arterial pressure (MAP) normally induced by facial immersion was tested. The purpose of this study was to investigate the cardiovascular control mechanisms associated with apneic facial immersion during different cardiovascular challenges. Six subjects randomly performed 30-s apneic facial immersions in 6.0 ±1.2°C water under: 1) -20mmHg lower body negative pressure (LBNP); 2) +40mmHg lower body positive pressure (LBPP); 3) during a period of post-exercise hypotension (PEH); and 4) normal resting (Control). Measurements included SkBF at 1 acral (distal phalanx of the thumb) and 1 non-acral region of skin (ventral forearm), HR and MAP. Facial immersion reduced HR and SkBF at both sites and increased MAP under all conditions (P<0.05). Reduced cardiac filling during LBNP and PEH significantly attenuated the absolute HR nadir observed during the control immersion (P<0.05). The LBPP condition did not result in a lower HR nadir than control but did result in a nadir significantly lower than that of the LBNP and PEH conditions (P<0.05). No differences were observed in either SkBF or MAP between conditions, however, the magnitude of SkBF reduction was greater at the acral site than at the non-acral site for all conditions (P<0.05). These results suggest that the cardiac parasympathetic response during facial immersion can be attenuated when cardiac filling is compromised.