A plasma display device having a structure that reduces the probability of breakdown of the signal transmitting unit. The plasma display device includes a chassis base, a PDP supported in front of the chassis base, a driving circuit board that drives the PDP and is supported on a rear side of the chassis base, and a signal transmitting unit that couples the driving circuit board and the PDP by detouring the chassis base, wherein the ratio of H/W of a separation distance H with respect to a distance W between a connection portion and a vertical portion of the signal transmitting unit is 0.075.ltoreq.H/W.ltoreq.0.500.