A hinge assembly is provided for a signal cable to pass through. The hinge assembly includes a first bearing block, a second bearing block, and a spindle. The first bearing block includes a first fixing plate and a first sleeve, the first sleeve is connected to a side edge of the first fixing plate, and the first sleeve has a first sectioned groove linked to its two ends. One end of the spindle is inserted in the first sleeve, and the other end is fixed on the second bearing block. The spindle has a second sectioned groove, and the second sectioned groove has at least one end linked to the first sectioned groove of the first sleeve, so that one end of the first sleeve, the first sectioned groove, and the second sectioned groove are linked to form an accommodating space for signal cables to pass through.