Introduction: Paclitaxel (PTX), an effective chemotherapeutic drug, is widely used to treat several types of cancers. However, its use is limited due to poor water solubility resulted in poor bioavailability. One of the main ways to increase the efficacy and endurance of medications depends on the carrier that used for it. In the current study, the microemulsions (MEs) were investigated based on Poly [2-methacryloyloxyethyl phosphorylcholine (MPC)-co-n-butyl methacrylate (BMA)-co-p-nitrophenyl-oxycrabonyl poly ethylene glycol-methacrylate (ME-ONP)] (PMBN) ability as a carrier for PTX to increase the half-life and its bioavailability. Also, the physicochemical properties of the ME system were evaluated. Materials and Methods: PMBN, tween 80, triacetin, and glycerol were used as the drug carrier, surfactant, oil phase, and co-surfactant, respectively. The hemolytic activity was characterized using the RBC hemolysis assay to evaluate the blood compatibility of the MEs. In addition, the in vitro cytotoxic effect of PMBN-PTX-ME and PTX on MCF-7, 4T1, and HFF-2 cell lines was performed. PI and Annexin-V dyes were used for cell apoptosis. Results: The conductivity of ME evaluated and the results showed 432 to 589 µ S/cm. In vitro, the drug release study revealed that PTX has controlled release at different pH levels. Refractive Index (RI) and % transmittance of the MEs remained ranging from 1. 43 to 1. 53, and 89% to 98%, respectively. The MTT assay determined that PMBN-ME without PTX had no significant toxicity on HFF-2, MCF-7, and 4T-1 cell lines. Based on the apoptosis assay, treated cell lines with PMBN approximately remained alive. Conclusions: The results revealed that ME-based on PMBN would be a promising drug delivery system for PTX drug delivery.