The structure parameter of sliding bearing has significant influence on entire shafting. The structural optimization of elliptical sliding bearing based on the genetic algorithm theory is studied in the paper. Shafting logarithmic decrement is taken as the objective function, the bearing width-diameter ratio, relative clearance and main design parameters such as ellipticity is taken as design variables. Mutual coupling effect between sliding bearing and rotor is considered in the optimization model. An elliptical sliding bearing of shafting has been optimized, and the solution result shows that the shafting stability has been increased, it indicates this method is feasible.