The investigation of the taste and odor compounds in Lake Taihu,from June 2009 to May 2010,included MIB,GEO, β-cyclocitral and β-ionone.Given comprehensively consideration to various environmental factors and cyanobacteria taxa,we analyzed the relationships between two forms of odors and some key environmental factors closely related with these odors.It was found that dissolved MIB and particulate β-cyclocitral,β-ionone were the main odors,and they made great contributions or potential contributions to odor problems in Lake Taihu.Combining previous studies with this investigation,it was estimated that the variations of production and release velocities of the odors,microbe degradations,photolysis,absorption and volatilization led to the weak relationships between the dissolved odors and the particulate ones.Microcystis and chlorophyll-a had close relationships with taste and odor compounds in Lake Taihu.Cyanobacterial blooms had important influences on occurrences of the taste and odor compounds in Lake Taihu.For managing the occurrences of taste and odor events,it is very critical to control cyanobacterial blooms.