Lake ecosystem health is the important embodiment of harmony between man and nature and the concept of sustainable development. Lake health evaluation matter-element analysis model was set up and its index weight calculation was improved by combining the analytic hierarchy process (AHP), entropy weight method and principal component analysis (PCA) method to construct the optimal combination weight method based on the principle of the sum of squared residuals. The health assessment of five lakes were evaluated using the method. 12 detailed indexes were selected to establish the evaluation system and evaluation standard according to the specific situation of the five lakes. With the calculation of the model, the results showed that, four of the five lakes were evaluated as excellent, one was good, overall level of local lakes health were fine. So the model is suitable and be regarded as an effective method for lake health evaluation.