To develop a green and safe drug-loaded carrier of chitosan, it is prepared with emulsion crosslinked by cinnamaldehyde of food grade. In this research, the resultant products and drug-loaded property were characterized by FTIR、SEM、UV-VIS and so on. The results are as follows： SEM shows microsphere good sphericity and dense surface; the crosslink reaction between the amino groups on chitosan and the aldehyde on cinnamaldehyde was confirmed in FT-IR spectrum.；the drug-loaded property was good, and the drug-loaded content and entrapment efficiency are respectively 22.3% and 91.2%. To compare formaldehyde and glutaraldehyde, Cinnamaldehyde is a new and safe crosslinking agent for drug-loaded chitosan microsphere.