A connection structure for an electric wire includes an electric wire that has a conductor and an outer sheath covering the conductor; a bonding member that is made of a conductive metal material and is attached to the electric wire and; and a busbar that is made of a conductive metal material and on which the bonding member is overlapped and ultrasonically bonded with the conductor interposed between the busbar and the bonding member. The bonding member includes a crimping portion for crimping and fixing the electric wire.