A preliminary study on the possible eutrophication and countm easures of Q iigpin Reservoir Deyang city, Sichuan Province, was carried out since 1990s.In this paper the data from four m onitoring river cross-sections in five continuous months showed that the concentration of TP is very high, up to 0.193-0.554m g°L^-1.The temporal and spatial distribution model of TP during initial stage of reservior operation, and method ofdefiniig parameters of model is discussed The model is applied to simulate the change of TP concentration during the initial stage ofQ inpin Reservior operation for two possible dams of Daqianpiig andPibayan.The smulated results showed that the concentration of TP exceeds standard ofwater quality for both dams, 0.042m g°L^-1 for the dam ofD aqianpiig, and 0.082mg°L^-1 for the dam of Pibayan, respectively.Hence the eutrophication will probably occur in Qinping Resevior after operation StilJ the eutrophication for Daqianpiig Dam would possibly be controlled conditioning some countermeasures be takein while that for Pbayan Dam would not under present sc-technical conditions