The initial boundary value problem of a elastic rod vibration system with damping and source term was studied.This problem came from the vertical vibration of a elastic rod in physics.By the theory of partial differential equation and the energy perturbation method
and by constructing auxiliary functions and differential inequality
it is proved the solutions are global under some conditionson growth ordersof the damping and the source term.The conditions are sufficient.The results are of the promotion of part literature.