The present invention discloses a low power dissipation Bluetooth mesh network system and a communication method thereof. The Bluetooth mesh network system includes a friend node and a lower power node. The friend node operates as a proxy server terminal to perform a proxy server broadcast. The lower power node operates as a proxy client and establishes a connection with the friend node based on a proxy protocol when the proxy server broadcast is received and identified. The friend node further filters out an invalid packet unrelated to the low power node and stores a valid packet related to the low power node so as to transmit the valid packet to the low power node when the low power node switches from a sleep status to a wakeup status.