Abstract: In order to find a proper material for temporarily sealing tritium-contaminated stainless steel, the surface morphology and specific surface area of neutral silicone sealant film were characterized in this paper. Base on it, the temporary sealing experiments were carried on modeling samples of tritium-contaminated 316L stainless steel with neutral silicone sealant. It shows that the influence of four factors such as film thickness, storage time, water leaching at different temperatures are not obvious.