Red Nile tilapia (Oreochromis niloticus) fish scales are known to contain gelatin with potential as a gelling agent in peel-off mask bases. Gelatin was extracted from red tilapia fish scales and characterized in comparison to commercial gelatin. The extracted gelatin was formulated as a gelling agent at concentrations of 6%, 8%, and 10% (F1–F3), and three additional formulations used commercial gelatin. The gel bases were evaluated for physical stability over 12 weeks under three storage conditions: room temperature, sunlight exposure, and 40°C. Parameters observed included organoleptic properties, pH, viscosity, spreadability, adhesiveness, and drying time. The fish scale gelatin appeared as yellowish powder with a viscosity of 16.40 and pH of 5.47, aligning with the Indonesian National Standard (SNI) for commercial gelatin. All formulations showed pH values within the skin's acceptable range and stable viscosity at room temperature, with minor changes under heat and sunlight exposure. There were no significant differences in spreadability, adhesiveness, or drying time. The formulation containing 8% fish scale gelatin exhibited the most stable performance. These results suggest that gelatin from red tilapia fish scales has comparable characteristics to commercial gelatin and is suitable for use as a natural gelling agent in peel-off mask formulations.