Natural sepiolite composites and selected sepiolite composites were prepared in liquid phase by intercalation, and the properties of composites were characterized by test analysis of TG/ DTA, SEM, XRD. Results show that a wide range of endothermic peak is between 30.0~ 40.0°C, their advisable scope of phase change temperature is 3.81°Cand 4.4°C respectively.LA-SA content in two kinds of sepiolite composites attain 42.3 wt% under the best component condition, their modified temperature is 80°C and room temperature respectively. The weight loss of the composites is no more than 2.0 wt% among phase change temperature. Two kinds of modified sepiolite as carrier have little effect on properties of composites, LA-SA content does more. A large amount of LA-SA is adsorbed effectivelly into internal pores or surfaces of modified sepiolite. In view of cost and resource,natural sepiolite has advantages over selected one. This research provides prospective applicaiton foundation for energy-saving building thermal storage composites.