This study presents the combination of the prodrug approach with the self-assembly technique by using a poly(ethylene glycol)–paclitaxel (PTX) conjugate as the nanomicellar carrier for delivery of free PTX drugs. The conjugate PEG-PCPGE/PTX readily forms stable micelles in aqueous solution and is used to form an intracellular pool of PTX after the micelles are endocytosed, where encapsulated drug is first released, then destabilized polymer–PTX molecules liberate free PTX following cleavage in the intracellular environment. The use of the conjugate PTX as the core of the micelles provides an ideal affinity site for free PTX, in the mean time, high drug loading and time-programmable delivery are realized.