 This study examined the effects of titanium dioxide nanoparticles on the performance of sunscreen creams. Three samples of titanium dioxide nanoparticles with varying sizes were tested for their ability to reduce the size of the particles, increase the dispersion of the particles in the cream, and improve the performance of the sunscreen. The results showed that the smaller particles, sample TA, had the most effective dispersion in the cream and the highest SPF rating. Additionally, the smaller particles had the greatest photocatalytic activity when exposed to ultraviolet light. This article was authored by Risa Gamapa, Akam Fala, and Maseed Jamshidi.