A data transmission method and a router, which are used to obtain a load sharing scheme according to current status information of a network, and perform data transmission according to the load sharing scheme in order to improve data transmission efficiency, where the method includes communicating, by a first router, with a second router over multiple radio links, acquiring, by the first router, status information of each radio link, determining a transmission overhead of each radio link according to the status information of each radio link, determining load sharing of each radio link according to the transmission overhead of each radio link, and sending data to the second router according to the load sharing of each radio link.