Disclosed are an elastic contact spring and an adapter using the contact spring, The elastic contact spring comprises two contact parts and a connecting part located between the two contact parts, the two contact parts are arc-shaped and their peripheral surfaces form jacking surfaces in conductive contact with corresponding connectors, the two contact parts are in transition connection via the connecting part and their respective arc-shaped openings are respectively located on two sides of the connecting part. When the elastic contact spring is pressed in use, the arc-shaped contact parts and the connecting part of the elastic contact spring all form deformation parts to disperse the deformation stress, thereby prolonging the service life of the elastic contact spring, and tho elastic contact spring, which is only formed by simple arcs, does not have a special requirement for materials.
