The objectives of the present invention include to connect a twisted pair cable to the electric connector without undoing the twist of the end of the twisted pair cable, to accurately keep the twist of the twisted pair cable up to the end thereof, to make the twisted pair cable fully exhibit its noise cancellation effect, and to maximize impedance matching. The electric connector for twisted pair cable using resin solder according to the present invention comprises a pair of electric contacts having the first connecting part, which fits with the counterpart connector, and the second connecting part, to which the conductor of the electric wire is connected, and an insulating member, which insulates and holds these electric contacts. In each of the electric contacts, at least a part of the second connecting part, to which the conductor of the electric wire is connected, is made of a lead-free ultrahigh-conductive plastic being a conductive resin composite.