<p>Aloe vera functionalized zinc oxide (ZnO) nanoparticles (NPs) are synthesized employing a simple wet chemical method, and different samples are synthesized with varying amounts of Aloe vera (AV) in the starting solution to tailor the ultraviolet (UV) ray-blocking proficiency. The line shapes of UV-VIS absorption spectra show remarkable gradual changes with varying experimental conditions. Photoprotection and photostability assessing parameters are measured, and based on these interesting results, aloe vera functionalized ZnO NPs are identified as the potential sun-blocking agent to be used in high-quality sunscreens. Moreover, it appears that the sun protection factor of NPs rises with increasing the amount of AV up to 20 mL. Furthermore, the antioxidant capacity of the AV-functionalized ZnO NPs increases and their photocatalytic activity decreases as the quantity of AV increases up to 20 mL. Compared to other synthesized samples, the sample synthesized with 20 mL AV in the starting solution has more effectiveness as a sunscreen agent. When compared with some commercial sunscreen brands, it appears that the photoprotection ability of the sunscreen made with the ZnO sample synthesized with 20 mL AV in the initial solution is greater than that of popular sunscreen products. On the other hand, the decay values of the sun protection factor and protection grade of UVA of the sunscreen made with the ZnO sample synthesized with 20 mL AV in the starting solution are found to decrease at a lower rate compared to that of sunscreen brands with increasing exposure time after placing them in the sun.</p>