This study was performed to derive the formula of sediment yield and predict the sediment elevation for fresh desalted reservoirs. Data analyzed was from 3 fresh desalted reservoirs of Sapkyo, Asan, and Namyang. Average sediment yield calculated from the sediment survey data was $279m^3/km^2/$ year for Sapkyo lake, $523m^3/km^2/$ year for Namyang lake, and $190m^3/km^2/$ year for Asan lake. The trap efficiency for Sapkyo lake was 63%. The formula of sediment yield was derived as $Q_s=6,461{ imes}A{^-0.44}$ for fresh desalted reservoir. Sediment yield in fresh desalted reservoirs was much higher than that in inland reservoirs located in the same watershed, because of long trap time in fresh desalted reservoirs.