Disclosed is a portable communication device including a housing, a first printed circuit board (PCB) disposed in the housing, a wireless communication circuit mounted on the first PCB, and a second PCB including a connection part connected with the first PCB, a first PCB portion extended from the connection part and having greater flexibility than the connection part, a second PCB portion extended from the first PCB portion and having less flexibility than the first PCB portion, a third PCB portion extended from the second PCB portion and having greater flexibility than the second PCB portion, a fourth PCB portion extended from the third PCB portion and having less flexibility than the first PCB portion, a signal line extended to the connection part along the first, second, third, and fourth PCB portions, and vias arranged in at least a partial area of the second PCB portion or the fourth PCB portion, wherein a portion of the signal line is located between some of the vias.