A new N-succinyl-chitosan derivative (NSC), which could be self-aggregated to form nanoparticles in distilled water, was synthesized by microwave irradiation and characterized by FTIR, element analysis, XRD and TEM. Hydroxycamptothecin (HCPT) used as a modal drug was successfully entrapped into the NSC nanoparticles. The size of NSC nanoparticles and HCPT-loaded NSC (NSCH) nanoparticles were around 30 and 200nm, respectively. The drug entrapment efficiency of NSCH reached up to 68.5% and the release of HCPT was biphasic with an initial burst effect followed by a subsequent slower release. In vivo studies, the NSCH nanoparticles showed tumor targeting and significant suppression of tumor growth after s.c. injection (close to the tumor) to mice bearing S180 sarcoma tumor. A histopathological analysis of the tumor tissues indicated that NSCH had a lethal effect on the sarcoma cell. The results indicated that NSC nanoparticles had potential as a local sustained delivery system for hydrophobic antitumor drug.