Abstract The toroidal magnetic field which is created by toroidal coils has ripples in torus space. This magnetic field ripple is important for plasma equilibrium and stability studies in tokamaks. In this paper, we have presented the investigation of interaction between the toroidal magnetic field ripple and Resonant Perturbation Field (RPF) using the COMSOL Multiphysics software in the tokamaks. We have simulated the amplitude of toroidal field ripples without and with RPF (with different q = m/n) (m = 2, m = 3, m = 4, m = 5, m = 2 & 3; n = 1). The simulations show that RPF lead to modulation of toroidal field ripples.