Plain weave polyester fabrics were treated with lipase enzymes; namely lipase Type II and lipolase 100LEX enzyme at different reaction conditions to enhance its dyeability with basic dye. Fourier Transform Infrared spectroscopic investigation proved the creation of carboxylic as well as hydroxyl groups as a result of controlled rupture of ester links along polyethylene terephthalate macromolecule. This led to improved dyeability with the cationic dye “Basic Red 18” as well as reactive dye “Reactive Red 120”. Physical as well as mechanical properties of the treated fabrics; namely wettability, moisture regain, and tensile properties, were assessed compared to those of the untreated one. No significant deteriorative action of the lipolase enzyme, under the used reaction conditions, was detected by scanning electron microscopy.