Abstract: Fish_bellied cable truss of point supported glazing has been widely used for the characters of lightness and transparency. And commonly it is systematically supported,when additional support is added,the structure is turned from symmetrical support into unsymmetrical support,the mechanical performance will be changed greatly because of its weak ability to resist unsymmetrical deformation,and more discussion will be needed. Therefore it was made that the static and dynamic performance of cable truss under unsymmetrical support with model experiment and theoretical analysis. At last it was given the referenced wind_induced vibration coefficient for design.