To　further　raise　the　application　level　of　flood　forecast　information　to　reservoir　operation,　this　paper　examines　reservoir　operation　schemes　based　on　net　rain　forecasting　through　a　case　study　of　Longjiaoshan　Reservoir　in　Shandong　Peninsula.　We　construct　a　commonly-used　Xin＇anjiang　model　for　this　reservoir,　and　evaluate　its　errorsusing　the　method　of　deterministic　coefficient　and　absolute　error　calculations.　And　the　pass　rate　is　adopted　to　evaluate　its　accuracy　gradingin　runoff　depth　predictions　and　peak　time　predictions.　The　results　show　that　this　model　features　with　all　the　evaluation　indexesat　grade　one　for　both　the　calibration　and　verification　periodsand　provides　a　reliable　tool　for　reservoir　operation　study.　Then,　we　formulate　an　operation　rulefor　the　reservoir　flood　control　by　using　its　predicted　net　rainfall　information　from　the　Xin＇anjiang　model,　and　calculateits　design　floods　of　different　frequencies.　Comparison　of　the　results　with　those　of　the　conventional　reservoir　operation　shows　that　the　forecast-based　operation　model,　through　predicting　reservoir　discharge　in　advance,　can　generate　operation　schemes　that　effectively　reduce　the　peakstages　and　peak　discharges　of　the　reservoir　and　decrease　its　downstream　flood　peaks.　This　means　a　great　significance　to　the　risk　reduction　of　flood　control　upstream　and　downstream　a　reservoir　and　the　improvement　onits　flood　control　benefits.　©　2020,　Tsinghua　University　Press.　All　right　reserved.