Abstract: A dataset of 54 lakes and reservoirs in Yungui Plateau Ecoregion was assembled. Total phosphorus (TP) and chlorophyll-a (Chl-a) reference conditions were derived from descriptive statistics approaches, such as reference lake approach, population distribution approach and trisection approach. Simple predictive models based on the morphoedaphic index (MEI) and empirical models, including unary linear regression model and relatively complicated multiple linear regression model, were developed for estimating reference TP and Chl-a concentrations. The results of both methods broadly agreed, and it was indicated that the reference conditions of TP and Chl-a concentrations in Yungui Ecoregion lakes and reservoirs were 0.01 mg/L and 2 mg/m³, respectively, which suggested that the reference conditions corresponded to oligotrophic-mesotrophic states.