Summary: This paper is firstly devoted to an SVIR epidemic model with different immunization rates, and the interval time of vaccination is analyzed using time delay. By using Lyapunov function, a threshold dynamics determined by the basic reproduction number \(R_0\) is established. It is proved that the disease-free equilibrium point is globally asymptotically stable when \(R_0 < 1\) and the endemic equilibrium point is locally asymptotically stable when \(R_0 > 1\). Furthermore, these conclusions are verified by numerical simulation.