OBJECTIVE: The purpose of this study was to investigate the immediate effects of traditional Thai massage (TTM) on psychological stress and heart rate variability (HRV). MATERIAL AND METHOD: Thirty healthy participants were randomly allocated in two groups, a TTM group (n = 15) who received a 1-hour session with moderate pressure of whole body TTM or a control group (n=15) who rested on the bedfor 1 hour All ofthem were given a 10-minute mental arithmetic test to induce psychological stress after which they received a 1-hour session of TTM or bed rest. Psychological stress and HR V were measured at baseline and immediately after mental arithmetic test, and immediately after TTM or bed rest. RESULTS: The studyfound that psychological stress was signficantly increased (p<0.05) after mental arithmetic test in both groups. Comparison on these measures between immediately after mental arithmetic test and after TTM or bed rest revealed that psychological stress was significantly decreased (p<0.05) and HR Vwas significantly increased (p<0.05) in both groups. Root mean square of successive differences (RMSSD) and low frequency were significantly increased (p<0.05) only in the TTM group. However; all of these measures were found without significant difference when groups were compared. CONCLUSION: TTM and bed rest could decrease psychological stress and HRV