The present invention provides a structure for clamping a built-in component in a hollow container, the container being formed by clamp molding using a pair of a first mold piece and a second mold piece, the first mold piece being for forming a first half of the container, the second mold piece being for forming a second half of the container, the structure comprising: a first support member secured to an inner wall surface of the first half of the container and having a first connection portion and a first clamp portion; a second support member secured to an inner wall surface of the second half of the container having a second connection portion and a second clamp portion, wherein the built-in component is clamped between the first support member and the second support member with the first connection portion and the second connection portion coupled to each other.