Abstract: Chitosan was prepared by alkaline N-deacetylation of squid pens β-chitin. Diethylenetriamine and epichlorohydrin modified chitosan microspheres (DECM) were synthesized via emulsion crosslinking using chitosan as monomer and diethylenetriamine and epichlorohydrin as crosslinker. The structure and properties of DECM were characterized by SEM, FT-IR, XRD and TGA, and the results show that DECM has large specific surface area and relatively more active sites. Adsorption of Congo red (CR) and Acid green 50 (AG50) onto the microspheres were studied with static adsorption, and the results show that the adsorption kinetics of two dyes follow the pseudo-second-order model. The maximal adsorption capacities calculated by Langmuir equation at pH 3.0 and 25℃ are 428.7 mg×g^-1 and 691.8 mg×g^-1, respectively. Freundlich model indicates that favourable adsorption mechanism can be applied for both dyes. Furthermore, anionic dyes adsorbed by the microspheres are successfully released using 0.1 mol×L^-1 NaOH and the adsorption capacity remains over 92% even after 5 adsorption-desorption cycles.