Fish protein hydrolysates (FPH) have demonstrated in vitro anti-hypertensive and antioxidant properties. Since hypertension and oxidative stress are key factors for endothelial dysfunction, the main purpose of the present study was to investigate the effect of FPH on vascular function. Participants consumed 5 g of FPH or a placebo (PLA) supplement. Flow-mediated dilation (FMD) and tissue O2 saturation (StO2) were taken at different time points over 130 min after nutritional intervention. The FPH had 80.6 ± 1.0% of protein and the major amino acid present in the FPH was glutamic acid, followed by aspartic acid and histidine. There was no significant change in FMD as well as no significant change in the StO2 parameters between FPH and PLA supplementation. Although FPH has been shown to be a valuable source of protein, essential amino acids and antioxidants, a single dose did not promote significant changes on vascular function in healthy individuals.