Deep water running (DWR) is frequently used in rehabilitation from sport‐related injury. Blood pressure (BP) response to DWR has not been determined. The purpose of this study was to determine if a reliable baseline BP measure may be obtained from a deep water runner and to analyze BP response to DWR. Three testers took three counterbalanced BP measures on 30 subjects at restonland and in water. Generalizability theory was used to determine reliability. The systolic BP (SBP)‐reliability coefficient ranged from G = 0.96 for three testers and trials to G = 0.81 for one tester and trial. The diastolic BP (DBP) reliability coefficient was G = 0.93 for three testers and trials and G = 0.74 for one tester and trial, respectively. As a follow‐up, 37 women performed 30 minutes of DWR at 70% of maximum heart rate. Heart rate and BP were measured at rest on land, in water, and every 5 minutes during DWR. There were no significant differences (p>0.05) between resting land and resting water BP. A repeated measures ANOVA indicated a significant (p≤0.05) increase in SBP only during the first 5 minutes of DWR. Diastolic BP did not significantly change from rest. Results indicated that a reliable measure of baseline BP may be obtained and that the BP response to DWR is similar to the reported BP response to land‐based exercise of similar intensity and duration.