Breast cancer remains the most commonly diagnosed malignancy in women worldwide, accounting for approximately 2.3 million new cases and 685,000 deaths annually. Docetaxel, a potent taxane chemotherapy agent, is severely limited by dose-limiting toxicity and low tumour selectivity. Curcumin exerts complementary anti-cancer activity through NF-kB and STAT3 pathway inhibition but is essentially non-bioavailable orally due to rapid hepatic metabolism. This study synthesises and optimises folate-conjugated PLGA-PEG nanoparticles co-loaded with curcumin and docetaxel using Box-Behnken RSM. The optimised formulation (FO) exhibits particle size 187.4 +/- 9.3 nm, PDI 0.183, zeta potential -28.4 +/- 2.3 mV, curcumin EE 78.4%, and docetaxel EE 82.7%. Sustained biphasic release reaches 93.7% at 72h following Korsmeyer-Peppas anomalous diffusion kinetics. Folic acid functionalisation achieves 3.8-fold enhanced cellular uptake in MCF-7 cells. Cytotoxicity IC50 values of 0.38 ug/mL (MCF-7) and 0.47 ug/mL (MDA-MB-231) are 5.6-fold superior to free drug combination, with combination index (CI) 0.31-0.42 confirming strong synergism.This work establishes folate-targeted PLGA-PEG co-delivery as a scientifically robust nanomedicine strategy for improving the therapeutic index of curcumin-docetaxel combination therapy in breast cancer