n order to investigate the wake interference of the staycables or the cables of suspension bridges without suspension rod, aerodynamic characteristic of two parallel cables were examined through a series of wind tunnel tests employing aeroelastic cable models. Cables with different spacing ratio W/D (where W is the spacing of centers of cables , D is the diameter of the cable ) , varying from 5.85 to 20 , and different wind yaw angle β, changing from -90°to 90°, were tested at uniform flow . Consequently, obvious wake galloping was observed in the experiment, and the results indicated that there was an prominent influence for wake galloping with the change of spacing ratio and wind yaw angle. The critical wind of wake galloping reduced with decreasing values of the spacing between the cable, and the outplane response of downstream cable was most dominant. The results also indicated that the yaw angle of 0°was the most disadvantage angle at same spacing , and it was easier for negative yaw angle to appear wake galloping than positive yaw angle.