A manufacturing method for an electric wire with a terminal includes: a first resin supplying step for discharging a curable resin material for internal use through a discharge port at a nozzle distal end after being caulked and crimped, and infiltrating the curable resin material for internal use into gaps between elemental wires while pressing out air in the gaps; a second resin supplying step for discharging a curable resin material for external use through the discharge port at the nozzle distal end, and covering the core wire exposed part in which the curable resin material for internal use is filled into the gaps, a core wire connection body, and a coating connection body with the curable resin material for external use from the outside; and a resin curing step for curing the curable resin material for internal use and external use by operating a resin curing device.