Sediment　cores　were　collected　from　the　central　and　northern　parts　of　Lake　Dianchi,　a　large　and　shallow　eutrophic　lake　situated　in　southwest　China.　Total　organic　carbon,　total　nitrogen　(TN),　and　total　phosphorus　(TP)　as　well　as　the　delta　C-13　and　delta　N-15　were　analyzed　in　the　sediment　cores.　Age　model　of　the　sediment　cores　were　established　according　to　Cs-137　geochronology,　which　reveals　that　the　sedimentary　record　covers　a　period　of　the　last　50　years.　During　that　time,　Dianchi　had　been　undergoing　a　distinct　conversion　from　oligotrophic　to　eutrophic,　as　a　result　of　increasing　nutrient　loadings.　The　two　cores　displayed　similar　increases　for　values　of　TN　and　delta　N-15,　and　the　variations　of　the　both　parameters　matched　well　with　that　of　TP,　which　presumably　suggested　that　delta　N-15　is　a　reliable　proxy　for　anthropogenic　nutrient　input.　Also,　dynamics　of　delta　N-15　and　TP　showed　that　anthropogenic　nutrients　input　seemed　to　start　in　the　1970s.　The　upward　elevation　of　delta　N-15　might　be　ascribed　to　the　increasing　input　of　isotopically　heavier　dissolved　inorganic　nitrogen　and　the　accelerated　denitrification　process　when　the　lake　water　was　oxygen-depleted.　The　less　variation　of　delta　N-15　in　the　uppermost　several　centimeters　of　both　cores　were　probably　the　result　of　pollution　controls　carried　out　by　the　local　government　in　the　recent　decade.　The　upward　increasing　of　delta　C-13　in　the　two　cores　seemed　to　be　induced　by　the　enhanced　productivity　since　1980,　which　was　in　accordance　with　limnological　observation.　Therefore,　delta　C-13　values　were　believed　to　be　an　effective　proxy　for　reconstructing　the　history　of　eutrophication　in　Lake　Dianchi.　In　addition,　this　study　also　suggested　that　carbon　and　nitrogen　isotopes　are　applicable　to　large,　shallow　lakes　in　interpreting　the　past　environmental　change.