Objective By using optical coherence tomography (OCT) to observe the residual subretina fluid changes in fovea that may explain visual recovery after anatomically successful repair of rhegmatogenous retinal detachments (RD). Design Prospective observational case series. Participants 34 patients(35 eyes) with successful retinal reattachment after macula involving RD repair. Methods 34 patients were followed up at 3 days, 15 days, 2 months and 6 months after sclera buckling. The best corrected visual acuity(BCVA), eye fundus status were recorded. The OCT images through the center of the fovea were obtained. Main Outcome Measures The OCT images and BCVA after RD repair. Results The BCVA and OCT images were obtained 3 days to 6 months postoperatively. There were 3 eyes, 5 eyes, 9 eyes and 23 eyes respectively with residual subfovea fluid absorbed totally at 3 days, 15 days, 2 months and 6 months. In the residual subforvea fluid group, the mean visual acuity increased at 0.124?0.013. In the subfovea fluid absorbed group, the mean visual acuity increased at only 0.019?0.006. Conclusions After anatomically successful repair of RD performend with sclera buckling, the minimal residual subforvea fluid will exist for a long time and will be absorbed slowly. This may explain slow increase of postoperative visual acuity after anatomically successful repair.