A microneedle unit is provided in which a direction from a bottom to an opening is a pressing direction, a recessed container is configured to allow deformation due to an external force in the pressing direction being applied to the bottom, and deformation of the recessed container includes displacement of the bottom in the pressing direction and displaces a projection in the pressing direction on the outside of a housing space, and an adhering section includes a first contact surface that is in contact with the bottom, and a second contact surface that is in contact with a support surface and extends from the support surface to an area surrounding the support surface, and the deformation of the recessed container causes the second contact surface in the area surrounding the support surface to be pushed out of the housing space via the opening.