In view of the plug-and-play requirements for a large number of smart devices in a smart grid， which results in the difficulties in setting up communication channels， a self-organizing communication mode in the smart grid based on geographical information is proposed.In this self-organizing communication mode， addressing is performed by all smart devices using geographical information. Routing and forwarding for data packets is implemented using geographical information. Depending on the information type， information fusion is realized in the process of forwarding data packets. A query algorithm is presented that automatically generates routing information in the process of enquiry and transmits information using the greedy algorithm. The test results verify the feasibility of self-organizing communication mode based on geographical information in a smart grid.