The physicochemical properties of paclitaxel and a novel amphiphilic polymer–paclitaxel conjugate P(LGG-paclitaxel)-PEG-P(LGG-paclitaxel) has been evaluated using Density Functional Theory (DFT) and Hartree Fock (HF) calculations. This complex was derived from its parent polymer P(LGG)-PEG-P(LGG), poly{(lactic acid)-co-[(glycolic acid)-alt-(L-glutamic acid)]}-block-poly(ethylene glycol)-block-poly {(lactic acid)-co-[(glycolic acid)-alt-(L-glutamic acid)]}. Our investigation include: geometrical parameters of paclicaxel and its polymer-base complex, NMR study of paclitaxel, binding energy, electric potential and electric field gradient of complex beside some other properties such as partition coefficient, polarizibility, hydration energy and etc. Our results indicate that the polymer-paclitaxel mentioned above can be used to improve anti cancer activity of paclitaxel.