Based on the analysis of the relationship between granularity of ground material and the tooth profile parameter of roller mill, Bond theory of power dissipation was selected to study power consumption of the roller mill. It showed that power consumption was affected by flute profile, material characteristics, roller speed, roll length, roll clearance, grinding time and the particle sizes before and after grinding. The relational graph of power consumption with tooth depth in break system was drawn up by Matlab and simplified properly, taking Ⅰ~Ⅳ break system as the research object, with roll clearance of 0.8, 0.6, 0.4, 0.2 mm, respectively. The results showed that the power consumption increased gradually with the increase of the wear extent of flute. When the wear reached a certain degree, the power consumption changed sharply. Since power consumption is one of the important indicators to judge whether the roller needs drawbench or to be changed, the power consumption mathematic model based on Bond theory provides reference for further study on the relationship between wear of tooth roller and energy consumption.