The purpose of this study were to investigate the influence of the water flow and wave against the supine floating(called "Tyakuiei" or "Uitemate" in Japanese) using the heart rate variability as an index of the autonomic nerve system activity and amylase value in the saliva and to have a resources for the water rescue and survival research. After 3 minutes supine floating in still water, subject tried to perform that floating with exposure on the artificial water flow or wave during 3 minutes. Between the both experiment, subject took a break for several minutes. The wavelength was almost 2.0m and wave height was 0.1m. Average heart rate was not much difference between still water and water flow (wave). High frequency of R-R wave interval in the electro-cardiograph in wave was higher than that in still water. Amylase value in water flow was higher than that in still water.