Provided is a connector including a connector terminal to which a mating terminal pin is connected and a connector housing configured to house the connector terminal therein. The connector housing has a tubular inner surface surrounding the connector terminal. The connector terminal includes elastic contact pieces arranged at intervals around a central axis of the tubular inner surface. Each elastic contact piece includes a contact portion extending along the central axis and being curved and a distal end portion located outward in a direction orthogonal to the central axis of the contact portion. The contact portion, when subjected to a pressing force from the mating terminal pin toward the tubular inner surface, is shaped into a flat form as a result of the distal end portion moving along the tubular inner surface. Also provided are an electric wire with the connector and a medical device sensor.