Paclitaxel (PTX), a taxane-based chemotherapy, has been applied clinically for the treatment of multiple types of cancer. To improve poor aqueous solubility of PTX and pharmacological performance, several delivery systems have been created. Polymeric micelles have evolved as a highly promising drug delivery platform via encapsulating poorly soluble therapeutic substances. In this study, we prepared a polymeric micelle encapsulating PTX by the thin film hydration method using clinically approved block copolymer such as polyethylene glycol-block-poly(D,L-lactide). The study aimed to prepare and optimize polymeric micelle formulations encapsulating PTX based on the film hydration time and its effect on the micelle particle size and drug loading. The results showed the particle size of less than 70 nm and higher encapsulation when the drug-polymer films were hydrated for 5 minutes at 60^oC. However, when hydrated longer than 5 minutes, micelle formation was disrupted and both drug loading and particle size in aqueous media were less than that of formulation hydrated for 5 minutes. These results indicate that optimizing the film hydration time is critical for achieving the desired particle size and drug loading in polymeric micelle formulations encapsulating PTX. Therefore, careful control of hydration parameters is essential to maintain the integrity and effectiveness of the drug delivery system.