Ultraviolet radiation from sunlight can cause skin redness and hyperpigmentation. Kale (Brassica oleracea var. sabellica) is known for its high flavonoid content, making it a promising candidate for natural sunscreen formulation. This study aimed to develop a kale leaf extract gel with protective activity against UV radiation, as indicated by the Sun Protection Factor (SPF). Kale leaf extract was formulated into a gel preparation at concentrations of F1 (1%), F2 (2%), and F3 (4%). The gel was evaluated for organoleptic properties, homogeneity, pH, viscosity, spreadability, and adhesion. Sunscreen activity was assessed using a UV-Vis spectrophotometer, measuring SPF, percentage of erythema, and percentage of pigmentation. The formulated gel showed acceptable physical characteristics, including thick consistency, yellow-brown color, typical kale aroma, and homogeneous texture. The viscosity values ranged from 8888-9443 mPa.s, with a pH of 4.5. The spreadability was measured in the range of 5.24-6.55 cm, and the adhesion was recorded at 2.5 seconds. The highest sunscreen activity was observed in F3 (4%), which achieved an SPF of 0.28, with erythema and pigmentation protection values of 79.1% and 79.2%, respectively, categorizing it as low protection. Although the gel product has a low SPF, kale leaf extract showed potential photoprotective activity.