The invention discloses a data transmission network and a data transmission method, and belongs to the field of petroleum well drilling technology. The data transmission network comprises a basic node and at least two successively-connected business nodes. One end of each of the successively-connected business nodes is connected with the basic node. Each of the business nodes is used for acquiring underground data and after acquiring its own token, ending the acquired underground data to the basic node in the opposite direction of transferring of the token. The basic node is used for sending tokens for the business node and acquiring the underground data sent by each of the business nodes. Thus, power consumption of an underground data transmission network can be reduced.