Abstract: The binary-drug loaded micelles(BDM)，in which paclitaxel(PTX) and docetaxel(DTX) co-solubilized with the monomethoxy poly(ethylene glycol)-block-poly(D，L-lactide)(mPEG-PLA) copolymer，were prepared and evaluated for their in vitro stability.It was found that the stabilities of paclitaxel and docetaxel single-drug loaded micelles(SDM) with a drug-loading content of 10% maintained in the period of 9 h and 1 h,respectively，whereas the stable period of BDM with both drug-loading content of 25% was up to 24 h.Moreover，the BDM showed better physical stability at high drug concentration(≥1 mg/mL) than low concentration(0.04 mg/mL).In addition,a network structure of the BDM was observed using transmission electron microscopy(TEM).Faster in vitro release of paclitaxel and/or docetaxel from the BDM was found if compared with those of SDM.BDM in the potentials such as high drug-loading content and excellent stability might be an alternative to the micelles design.