[Problem to be Solved] To provide an indwelling device capable of aspirating a lesion easily into the indwelling device, and preventing leakage of the lesion to the outside and necrotizing the lesion reliably after hold of the lesion in the indwelling device, and to provide an indwelling device capable of preventing leakage of a lesion to the outside and holding the lesion reliably even if the lesion is relatively large in volume.[Solution to Problem] An indwelling device 1 is configured with a hollow tubular body, and includes a device body 5 and a device tip portion 3 connected to the tip of the device body 5 and made of an elastic member.
