The aim of this study was to examine changes of plasma aldosterone concentration during rehydration after heat stress. This experiment consisted with three circumstances of effective rehydration accepting in early phase: water consumption (DH/T-H₂O), isotonic solution (DH/T-GET) and (DH/T-NF) or without supplementing drink during early phase (0-2h) of rehydration to replacement water lost after heat stress. After 2h recovery to 24h rehydration all subjects intake water ad libitum. The subjects were exposed to heat stress (HS) for 60 min in a sauna bath (80 °C, rh 25%) and then rehydrated to 24h. Heat stress caused an increase of body temperature (1,6 °C), reduction of body mass (1%), reduction of plasma volume (3%) and significant increase of plasma aldosterone concentration. With start rehydration plasma volume increased. Aldosterone concentration at 24h recovery was significantly lower in DH/T-GET in comparison to DH/T-NF group, however did not differ significantly from DH/T-H₂O group. Results obtained in this study showed, that kind of consumed drink during early phase of rehydration did not influence significantly on plasma aldosterone concentration after heat stress. Increase of effectively rehydration in restoration whole body water balance limits aldosterone secretion after heat stress