Musty　and　earthy　substances　represented　by　2-methylisoborneol　(2-MIB)　are　important　pollutants　not　only　affecting　the　water　quality　but　also　threatening　the　security　of　drinking　water　sources　in　lakes　and　reservoirs.　In　this　study,　we　investigated　the　spatial　and　seasonal　distributions　of　2-MIB　in　waters　of　Lake　Yangcheng,　a　large　eutrophic　shallow　lake　in　China.　Driving　factors　affecting　the　production　and　accumulation　of　2-MIB　were　further　analyzed.　The　results　showed　that　2-MIB　concentrations　in　Lake　Yangcheng　ranged　from　0.4　to　940.6　ng/L,　with　a　high　annual　average　concentration　of　35.6　ng/L.　Distinct　seasonal　and　spatial　variations　of　2-MIB　were　found　in　the　lake　waters.　Specifically,　2-MIB　concentrations　were　highest　in　summer,　followed　by　spring　and　autumn,　and　lowest　in　winter,　whereas　2-MIB　concentrations　generally　exceeded　the　odor　threshold　(＜　10　ng/L)　in　the　first　three　seasons.　Spatially,　2-MIB　concentrations　were　highest　in　the　eastern　lake,　and　followed　by　the　central　and　the　western　lake.　The　environmental　conditions　of　a　higher　water　temperature　and　lower　TN:TP　ratio　(TN:TP　＜　29:1)　were　more　favorable　to　the　production　and　accumulation　of　2-MIB　in　Lake　Yangcheng.　The　algal　abundance　analysis　and　correlation　analysis　showed　that　cyanobacteria　species　including　Microcystis　spp.　and　Phormidium　spp.　were　closely　related　to　the　production　of　2-MIB　and　were　considered　as　the　main　driving　factors　of　the　accumulation　of　2-MIB　in　Lake　Yangcheng.　Therefore,　controlling　the　eutrophication　level　and　algal　blooms　are　of　great　importance　to　alleviate　2-MIB　pollution　in　lake　waters.