The study focused on enhancing cotton fabrics using modified starches dyed with an acid dye. The study will analyze and discuss various factors related to dye-ability, colorimetric data, color strength, fading and fastness characteristics. The study will include fastness grade, fading rate order curves, and fading rate constants. Since cotton is the most abundant raw material but has no affinity towards acid dyes. Lot of research and technological works were applied to increase its applications for the different end uses and upgrading its performance to become multifunctional, and accepting different classes of dyes. Samples were finished with (DEAE-O and / or-H) starches and dyed with a blue acid dye at different dye concentrations, then exposed to artificial daylight for different periods. The obtained results showed that treating cotton samples with the aminated starches rendered them accepting acid dyeing with considerable (k/s) and colorimetric values, good light fastness, and low fading rate constants values. The (C.F.G.) curves were linear with positive slopes and the examined fading rate curves showed class (2) fading order. The (k/s), the blue component (-b), the (L.F), and the (tf) 10% values were in direct proportion with the dye concentrations, while [K, ∆ E] values showed the opposite trend. It was concluded that, the values of the blue component (-b) may be taken to represent the actual blue color of the applied dye on the fabric. Also, (K) could be taken as good representation to the light fastness compared to the recorded L.F. ratings values.