A foreign substance removing device includes a tubular member and a retriever configured to be expandable to and contractible from a predetermined shape. The retriever includes main wires disposed to be centered around a tube axis of the tubular member, and sub wires each connecting adjacent ones of the main wires to each other. Each of the main wires is configured to curve when the retriever is expanded such that a space having a predetermined size is provided by the main wires. Each of the sub wires is configured to be foldable at at least one point between the adjacent ones of the main wires. When the retriever is expanded, the folding points of the sub wires are positioned inside the space such that the sub wires do not protrude out of the main wires.
