A reservoir is one of the most efficient measures for integrated water resources development and management. The reservoir storage curve is a vital parameter for multipurpose reservoir operation and its precision is a key issue for water balance and strategic risk management. Compared with the traditional approach, the method based on remote sensing (RS) data provides better information, which can be helpful in reservoir operation and management. Fengman Reservoir was chosen as a case study to obtain the new storage curve that is based on LandSat data. The inflows of the reservoir were calculated in dry seasons (December, January, and February) from 1958 to 1986 on the basis of the designed storage curve and the new estimated curve, respectively. Compared with the observation data, the average relative error of inflow using the new estimated curve is much less than one using the designed curve. The results showed that reservoir storage curve estimation based on RS data is reasonable and has relatively high precision.