A wireless network system and a wireless access point (AP) device thereof are provided. The wireless network system includes at least a wireless AP device and a plurality of wireless terminal devices. Each wireless AP device maintains a load list including load states of all wireless AP devices in the same area, and ranks load states of all wireless AP devices in the load list at least according to central processing unit utilization rates of the wireless AP devices. When a wireless terminal device transmits a connection request to one wireless AP device, the wireless AP determines whether it being in a low load state, and decides, depending upon whether it being in the low load state, to accept the connection request or to notify one or a plurality of wireless AP devices being in the low load states in the same area to accept the connection request.