Abstract: According to the 24 hour water temperature data from Bangong Co and Dagze Co,both located in the Tibetan Plateau,during August,2012 to August,2013,we discussed the characteristics of water temperature and dynamic processes of the two lakes.The analysis of the water temperature during different periods shows the following results.(1)Laterally,the water temperature of two lakes reached maximum in August with an obvious seasonal change,varying from a minimum 0℃to a maximum 17℃.Meanwhile,it showed an unapparent daily change varying below 1℃.(2)Longitudinally,Bangong Co just stratified at the depth of 20 min summer but Dagze Co stratified at the depth of 16 mduring the whole year.This indicated that Bangong Co is a dimictic lake and the Dagze Co is a typical meromictic lake.Based on the theory of fractal and R/S method,the time series of water temperature from 2012 to 2013represented longrange positive correlation and the structure of Bangong Co would persist in the future.