Objective: To explore accuracy and validity of a VO₂max prediction equation of the multistage model using by modified Bruce protocol submaximal exercise test in healthy subjects. Method: Thirty three healthy subjects (age: 44.0±12.9) were recruited. VO₂max was measured during treadmill by direct gas analysis from a maximal incremental test. VO₂max was then predicted from multistage model equation with age, measured oxygen consumption and heart rate during a maximal incremental treadmill test. And the predicted VO₂max values from equation were compared with the measured VO₂max values. Results: The predicted VO₂max values and the measured VO₂max values were highly correlated (r=0.9, p＜0.001). The predicted VO₂max values (2,285.3±536.0 ml/min) were not significantly different from the measured VO₂max values (2,285.5±598.5 ml/min). Conclusion: In healthy subjects, the multistage model equation offers a fairly accurate VO₂max prediction. Therefore the equation can be used in the estimation of VO₂max at modified Bruce protocol in an aerobic exercise program. (J Korean Acad Rehab Med 2008; 32: 549-552)