Background: Stroke volume variation (SVV), a dynamic index, shows high sensitivity and specificity in predicting the fluid responsiveness of patients undergoing mechanical ventilation. Previous studies have shown that SVV-oriented fluid management performs positive effect in the perioperative maintenance of hemodynamic and better prognosis. It also could be used to predict the fluid responsiveness under one-lung ventilation with constant volume. The present study was aimed to determine the feasibility of stroke volume variation as a predictor for fluid responsiveness under pressure-controlled one-lung ventilation. Methods: Seventy patients were enrolled and divided into two groups with distinct ventilation pressures (20 cmH(2)O and 25 cmH(2)O). ROC curve analysis was performed to evaluate the capacity of SVV for prediction. Results: Sixty-three out of 70 patients completed the study. SVV showed weak correlation with dSVV and dSVI. The optimal threshold value of SVV to discriminate between responders and nonresponders was 9.5% (sensitivity 75.6% and specificity 54.5%). The optimal threshold value of SVV to discriminate between responders and non-responders remains to be 9.5% for both subgroups with 20 cmH(2)O and 25 cmH(2)O. Conclusion: SVV is a poor predictor of fluid responsiveness for patients undergoing pressurecontrolled one-lung ventilation.