[Objective] To effectively prevent the irreversible water pollution and damage in Baihua Lake in the karst plateau region, the lake was taken as a research object and its water quality and changes over years were studied. This was aimed to provide a basis for the scientific development, utilization, and protection of the water source for relevant water resource management departments.[Methods] Based on an analysis of the physical and chemical parameters of the eight water bodies in Baihua Lake from 2013 to 2016, and to ensure that the water quality evaluation results were as objective as possible, the fuzzy comprehensive evaluation and grey correlation analysis methods were used to comprehensively evaluate the water quality of Baihua Lake and to reveal the category that its water quality could be classified.[Results] Baihua Lake had class Ⅰ water quality, but the class Ⅱ, Ⅳ, and Ⅴ values were relatively high.[Conclusion] The quality of water in Baihua Lake is getting worse. It is imperative to propose countermeasures to stabilize the ecological environment.