The aims of this paper were: a) to present weight reduction habits of adolescent wrestlers; b) to establish differences in mood states between weight groups; and c) to determine relations between weight loss and indicators of hydration with mood states. Adolescent wrestlers do resort to rapid weight loss (RWL) regimens in their training process and competition – 70.1% of the subjects reduced their body mass and the reduction regime usually lasted one week. Similar habits have been reported in other studies despite the well evidenced detrimental effects of RWL. Urine specific gravity (USG) values suggest that all the subjects were in the state of dehydration ranging from a mild to a high one. The groups of low weight (LW) and middle weight (MW) wrestlers reduced their body mass significantly more than others (BM; p<.05) and their sensation of fatigue was significantly higher (p<.05). The variables body mass reduction and %BM reduction were correlated with negative mood states, whereas the indicators of hydration in one of the groups (MW) established ambiguous relations with dehydration and positive mood states.