An HDMI connector structure includes a base, a circuit board, a chassis and a metal casing. The base includes a containing space, a retaining wall formed at a front end of the containing space, and an opening formed on the retaining wall. The circuit board is installed in the containing space, and an end of the circuit board is passed through the opening and out of the retaining wall, and at least one surface of the circuit board has a plurality of conductive pins, and a transmission line segment is extended from an end of each conductive pin and electrically coupled to a conductive terminal The metal casing includes a hollow main body, and the base is installed in the empty main body, and a front end of the hollow main body is provided for exposing a port from an end of the circuit board.