A support film for a tape material includes a film-shaped support formed of polyurethane and a barrier layer which includes aromatic isocyanate-based polyurethane and a layered inorganic compound, the barrier layer being formed on a surface of the support.一種貼布材料用支撐薄膜,其具備:由聚胺基甲酸酯所構成之薄膜狀的支撐體、及含有芳香族異氰酸酯系聚胺基甲酸酯與層狀無機化合物且形成在前述支撐體之一側的面的障蔽層。