Provided are a data flow distribution method and a controller. The method includes: a software defined network (SDN) controller acquiring data flow description information of a data flow; and the SDN controller deciding, according to the data flow description information, whether the data flow needs distribution, and when the data flow needs the distribution, delivering a distribution rule flow table to a distribution gateway. By using the technical solutions, application/service data flow based distribution is implemented. Compared with the related art that distribution is implemented based on a PDN connection and based on a bearer, the technical solutions implement finer-granularity distribution, and improve experience of users and competition of operators.