The invention discloses a method for building tree-shaped route in a wireless Ad Hoc network for power distribution and utilization. The method comprises the following steps: a node in a gateway node signal coverage scope is used for local broadcasting, routing requests are sent to neighbor nodes, routing response messages are sent after the routing requests are received by the neighbor nodes, path consumption value for a path reaching a gateway node via the neighbor nodes is calculated after the routing response messages are received by the node, a node with minimum path consumption value is chosen as a father node, corresponding channel information is added in an apply-to-join message packet which is then sent to the father node, a routing table is modified after the apply-to-join message packet is received by the father node, a chosen channel carried in the apply-to-join message packet is distributed to an idle interface, and the node reaching a destination of the gateway node sends a notify-upper-level-to-join message packet to an upper level. A route built via the route building method disclosed in the invention is robust, and recovery can be realized as soon as possible or switch to other route for transmission can be made when node faults and path failures occur.