The article presents a comprehensive index formula with power function for evaluating lake eutrophication, and the Hybrid Taboo Search (HTS) algorithm was also presented in order to optimize the parameters in the formula. Here, Hybrid Taboo Search is set up through combining Taboo Search with Simulated Anneal and Immune Arithmetic. The optimized formula was used in evaluating the level of ten sections in Donghu Lake. The results show that the model can describe the nature level of eutrophication well, and has indicating availability and simplicity for evaluation.