Mobile terminal device

A mobile terminal device comprising:

• two casings, each containing a circuit board, connected through a connecting unit to be able to overlie one another;
• a signal-line flexible board that is provided through the connecting unit to connect the circuit boards of the casings;
• and
• a pair of frame-grounded flexible boards that are formed wider than the signal-line flexible board to have a conductor pattern frame grounded, and sandwich both outer surfaces of the signal-line flexible board therebetween,
• wherein the frame-grounded flexible boards have a reinforcement of a nonconductor material on both sides of an outer surface not facing to the signal-line flexible board, and edge faces of the reinforcement wider than the signal-line flexible board are intermittently peeled in the longitudinal direction of the frame-grounded flexible boards to expose the conductor pattern.