Objective:To prepare and characterize docetaxel-loaded nanoparticles(Doc-np) and to evaluate antitumor efficiency of Doc-np in vivo and in vitro. Methods: Doc-np was prepared by nano-precipitation method. Particle size was detected by dynamic light scattering,and the form was observed by atom force microscopy and transmission electron microscopy. Drug load content and encapsulation efficiency were measured by UV. In vitro release curve was also spotted. In vitro cytotoxicity was performed by MTT assay. Nude mice with transplanted tumor were used to measure the in vivo antitumor efficiency of Doc-np. Results: It was found in our study that Doc could be incorporated into the nanoparticles with high encapsulation efficiency more than 90%. In vitro release study showed that Doc was released from Doc-np in a sustained manner,and cytotoxicity studies indicated that IC50 of Doc-np against SKOV3 cells was significantly lower than that of free Doc. Furthermore, intratumoral administration was applied to improve the tumor-targeted delivery in the evaluation in vivo. Compared with free Doc, Doc-np exhibited superior antitumor effect by delaying tumor growth when delivered intratumorally. Conclusion: These results suggest that Doc-np are effective to inhibit the growth of human ovarian cancer, and intratumoral delivery of Doc-np could be a clinically useful therapeutic regimen and merit more research to evaluate the feasibility of clinical application.