Concentration of chlorophyll-a (Chl. a), total phosphorus (TP), total nitrogen and water temperature are the four main driving factors resulting in eutrophication in Meiliang Bay, Lake Taihu. Based on the observation data in the period of 1992 -2010, the temporal pattern characteristics of the four factors in different temporal scales were analyzed respectively using wavelet analysis. Results showed that the temporal patterns of the four factors were obvious in the inter-annual and inter-decadal scales and the primary periods were different, but the real parts of wavelet coefficients of Chl. a and TP were consistent. The distributions and the periodic oscillation were analyzed and it was predicted that the eutrophication condition in Meiliang Bay would keep stable in the future 3-5 years. This method will provide reliable scientific evidence to the management of Lake Taihu.