OBJECTIVE： To prepare redox-responsive pluronic F127 micelles with high drug-loading efficiency. METHODS： The thiol derivative F127-SH with strong hydrophobicity was synthesized by introducing tert-butyl methacrylate and cysteamine to the hydrophobic segments of F127. Paclitaxel （PTX）-loaded redox-responsive pluronic F127 micelles with high drug-loading efficiency （F127-SS/PTX） were prepared by film-hydration method as well as oxidation reaction of thiol groups. The diameter， encapsulation efficiency and drug-loading amount were detected， and the change of diameter and drug release behavior of micelles were investaged under reducing environment or non-reducing environment. RESULTS： Mean diameter of F127-SS/PTX micelles was about （77.87±1.79） nm， and encapsulation efficiency and drug-loading amount were （92.73±2.35）％ and （16.25±0.99）％， respectively. The diameter of the micelles increased rapidly and drug release rate of PTX increased significantly in the presence of 10 mmol/L dithiothreitol. CONCLUSIONS： The redox-responsive pluronic F127 micelles with high drug-loading efficiency are prepared successfully.