Facing the issue of selecting rolling process parameter for high-precision titanium alloy bolts, the finite element simulation model is built for the rolling at root fillet of bolt. The distribution law of residual stress at root fillet of bolt after rolling is studied. The effects of rolling speed, processing time, friction coefficient, coating thickness and rolling force on the distribution of residual stress are analyzed and the optimal choice of rolling parameters is obtained. Moreover, targeting on the goal of minimizing the median integral of residual stress in root fillet rolling, the mathematical model of rolling parameters and residual stress is established in accordance with the simulation results. The optimal process parameters of rolling strengthening for the root fillet of high-precision bolt are obtained through parameter optimization. Moreover, the finite element simulation and experimental verification are carried out to validate the optimal results. The research results can offer theoretical guidance and technical support for the fillet rolling strengthening technology of highprecision bolts.