Provided is a gel composition with which a protective tube or cable can be easily filled during cable production; which has a high dropping point (temperature of the change from a semisolid to a liquid); which exhibits a behavior whereby the filler does not outflow from the interior over a broad temperature range, even when the protective tube or cable has been ruptured; and which can stop the infiltration of water into the interior. The gel composition contains (a) a base oil and (b) a hydrogenated block copolymer. The hydrogenated block copolymer (b) is the hydrogenate of a diblock copolymercomprising a polymer block (A) composed mainly of a structural unit derived from an aromatic vinyl compound and a polymer block (B) composed mainly of a structural unit derived from a conjugated diene compound. The content of the polymer block (A) in the hydrogenated block copolymer (b) is 38.0-45.0 mass%, and the content of the hydrogenated block copolymer (b) in the gel composition is 1-20 parts by mass per 100 parts by mass of the total of the base oil (a) and the hydrogenated block copolymer (b).