In order to model the electromagnetic logging responses while drilling with tool eccentricity and to provide theoretic basis for the eccentricity correction,the responses with tool eccentricity were simulated and analyzed based on the finitedifference time-domain( FDTD) framework. Non-uniform gridding technique in cylindrical coordinates and staircase approximation technique were utilized to reach fine simulation of borehole,coils,tool eccentricity. In addition,the UPML absorbing boundary condition was impl...