Two types of new cable-supported bridges using pipe girders and steel orthotropic decks were proposed; two-pipe-girder bridges with two cable planes and three-pipe-girder bridges with one cable plane. The suspension bridge with a main span of 750m and the cable-stayed bridge with a main span of 500m were designed and validated to be feasible. Wind tunnel tests were then conducted for these bridges. The torsional flutter occurred at the non-dimensional wind speed of about 4.5 for the two-pipe-girder bridge, which was higher than that of the pipe girder with RC slabs. The three-pipe-girder bridge shows superb aero-dynamic properties.