A new thermosensitive hydrogel had been prepared that could be transformed into gel at 37 °C from chitosan and a mixture of α- and β-glycerophosphate (αβ-GP). The appearance of hydrogel was compact and corrugated. There was little granule in the appearance of gel loaded with adriamycin and the granules might be crystals of the added model drug. In vitro cytotoxicity of the hydrogel was tested by the MTT method using mouse embryonic fibroblasts (MEF). MEF cultured with leachates of CS-αβ-GP were investigated and the relative growth rate (RGR) was calculated and the cytotoxicity was graded by generally accepted standard. The study of in vitro degradation of CS-αβ-GP hydrogels included hydrolysis and degradation by lysozyme. The CS-αβ-GP thermosensitive hydrogel was degradable in vitro and the degradation rate was faster in lysozyme solution than that in the medium of PBS. So the CS-αβ-GP system had good cell biocompatibility and biodegradability which provided possibilities and foundations for the further research.