Power-saving is one of the important issues in wireless sensor networks and many studies on power-saving in wireless sensor networks have been done. However, most of these studies have focused on saving power in gathering the information. In this paper, we tackle the issue of the energy-efficient information dissemination in wireless sensor networks. We propose method of disseminating information while optimizing electric power consumption in wireless sensor networks. Our new dissemination method employs flooding and uses the receiver signal strength to determine the broadcast timing. In our method, the node farthest from the sending node will rebroadcast the message first and a broadcast is canceled when a node scheduled to broadcast receives a duplicate of the scheduled message from other nodes. We evaluate our proposed method by simulation. As a result, it is found that the electric power consumption of the proposal method in the entire network is one-third that of the flooding method at the maximum. Furthermore, we show that the farther the transmitting distance of the wireless radio wave becomes, the more efficiently our method can disseminate information to the network.