In this research pure cotton textile was modified with zinc oxide nanosol prepared by the sol-gel method to improve ultraviolet light protection properties of natural textile. The cotton fabric was dipped in the nanosol solution prepared with zinc acetate dihydrate for 10 minutes, dried at 90 ºC for 10 minutes with further thermal post-treatment at 100ºC, 120ºC, 140ºC and 160ºC for 2 minutes. Comparison of coating of samples prepared using 7.5% concentration of zinc acetate dihydrate with different thermal post-treatments was made. Before and after laundering tests ultraviolet light protective properties of the textile samples were determined according to the standards, results show that textiles after treatment have excellent ultraviolet protection properties, as well treated samples after laundering tests (50 washing-drying cycles) still provide excellent ultraviolet protection. Analyses based on the scanning electron microscopy and spectrophotometer measurements show that obtained textile coatings are distributed evenly, not only on the surface of yarns but in the depth of textile material as well, and are resistant to exploitation process that indicates very good adhesion between the coating and the fabric surface.