Generally blended fabrics can satisfy the specific needs of a clothing material in terms of comfort and aesthetic value; however some blends lack uniform functional properties due to differences in their chemical properties. A study was carried to apply an ultraviolet protection finish by titanium oxide nanoparticles based emulsion on 50/50 silk/lyocell intimate blended fabric. The functional finishing process has been optimised by a design of experiment using Box and Behnken model with three variables such as concentration of TiO2 nanoparticles, padding time and curing temperature at three levels. The ultraviolet protection factor, tensile strength, air permeability, bending length, water absorbency and surface morphology of finished fabrics were evaluated; followed by regression analysis for optimisation in statistical software Design Expert 8.1. The optimum condition for UV protection finishing on silk/lyocell blended fabric was 5.85% TiO2, 35 min padding time and 98 °C curing temperature and the respective finished fabric sustained its desirable functionality up to 15 washing cycles.