A resin-made hollow container that is a vehicle fuel tank formed out of a first half (Ta) and a second half (Tb) of the container, which are mold clamped, the container being formed by mold clamping using a pair of a first mold piece and a second mold piece, the first mold piece being for forming the first half (Ta) of the container, the second mold piece being for forming the second half (Tb) of the container, the container comprising: a built-in component (7A, 7B), and a structure for clamping the built-in component (7A, 7B) in the hollow container, the structure comprising: a first support member secured to an inner wall surface of the first half (Ta) of the container and having a first connection portion and a first clamp portion; and a second support member secured to an inner wall surface of the second half (Tb) of the container and having a second connection portion and a second clamp portion, whereby the first connection portion and the second connection portion are coupled to each other. characterized in that the built-in component (7A, 7B) is clamped in the hollow container between the first clamp portion and the second clamp portion in the state that the first connection portion and the second connection portion are coupled to each other, so that the built-in component (7A, 7B) is stably secured to the hollow container via the first support member and the second support member that are coupled to each other. a built-in component (7A, 7B), and a structure for clamping the built-in component (7A, 7B) in the hollow container, the structure comprising: a first support member secured to an inner wall surface of the first half (Ta) of the container and having a first connection portion and a first clamp portion; and a second support member secured to an inner wall surface of the second half (Tb) of the container and having a second connection portion and a second clamp portion, whereby the first connection portion and the second connection portion are coupled to each other. characterized in that the built-in component (7A, 7B) is clamped in the hollow container between the first clamp portion and the second clamp portion in the state that the first connection portion and the second connection portion are coupled to each other, so that the built-in component (7A, 7B) is stably secured to the hollow container via the first support member and the second support member that are coupled to each other. a first support member secured to an inner wall surface of the first half (Ta) of the container and having a first connection portion and a first clamp portion; and a second support member secured to an inner wall surface of the second half (Tb) of the container and having a second connection portion and a second clamp portion, whereby the first connection portion and the second connection portion are coupled to each other. characterized in that the built-in component (7A, 7B) is clamped in the hollow container between the first clamp portion and the second clamp portion in the state that the first connection portion and the second connection portion are coupled to each other, so that the built-in component (7A, 7B) is stably secured to the hollow container via the first support member and the second support member that are coupled to each other.