Abstract：Earthquake cycles based on the site of the 2011 MW9.0 earthquake in Tohoku, Japan was simulated with a 2D finite element model in which motions of the fault is controlled by a slip weakening friction law. The numerical results show that earthquakes occur in a typical pattern of characteristic earthquakes: there are 6 large earthquakes during the 1 000 a simulation, the intervals between two adjacent earthquakes are about 161±4 a, and the seismic moments of per unit length for each earthquake is about 1.13×1020 Nm/km. There is a small earthquake with a seismic moment of 5.62×1018 Nm/km occurred between each two-adjoin large earthquakes. The coseismic and interseismic surface deformations of the numerical model agree well with the GPS observations. The uncertainty of the elastic parameters has limited effects on the coseismic and interseismic deformations, while variations of the viscosity influence the interseismic deformations. The numerical results also show that if the interseismic deformations were only controlled by the motion of the fault, the gravity anomaly of this model would decrease linearly during the interseismic period and reach about -370 μGal at about 100 km from the trench on the continent. Variations on velocity mainly happened within the first 5 a and velocities change little about 5 a after each earthquake.