Polyethylene terephthalate /Montmorillonite clay nanocomposite was prepared using commercially modification Montmorillonite (MMT). The prepared nanocomposite was characterized using scanning electron microscope (SEM). Fibers of pure Polyethylene terephthalate (PET) and Polyethylene terephthalate /montmorillonite clay nanocomposite (PET/MMT) were produced using melt spinning technique. Grafting of Acrylic acid was performed using grafting emulsion polymerization technique to obtain PET/MMT-g-AA fibre and the prepared fibers were characterized using mechanical properties, FTIR in addition to SEM analysis. The results show that the PET/MMT-g-AA fibre have higher mechanical properties, and lower water absorption than pure PET and PET/MMT fibers in addition to high degree in homogeneity between PET and MMT clay in PET/MMT fibre. Clindamycin drug was successfully loaded into PET, PET/MMT and PET/MMT-g-AA fiber via solvent immersion method with different drug fiber ratio in presence of glyoxal crosses linker. Drug release profile was studied for 120 min and the results showed that about 41% from the initial loaded drug was released from the fiber after an hour of release starting time.