The invention discloses a broadcasting method and a broadcasting device for a wireless ad hoc network, and belongs to the technical field of wireless communication. The broadcasting method comprises the following steps: obtaining, by a first wireless node, whole network routing information of the wireless ad hoc network, and selects a gradient center point; obtaining a whole network gradient value; determining a sending time slot according to the whole network gradient value, wherein when the first wireless node is a gradient center point, the sending time slot comprises a diffusion time slot,and sending, by the gradient center point, a broadcast message cluster in the diffusion time slot; when the first wireless node is a wireless node other than the gradient center point, the transmission time slot comprises an aggregation time slot and a diffusion time slot, sending, by the first wireless node, a broadcast message to a second wireless node in the aggregation time slot; and sending,by the first wireless node, a broadcast message cluster to the second wireless node in the diffusion time slot. Each wireless node can determine its own transmission time slot by itself without sending a request to the central node and waiting for the central node to allocate time slots for multiple wireless nodes, thereby improving the real-time performance of the broadcast transmission.