A uniform nonlinear resonant condition for interaction between electrostatic wave and charged particles in a uniform magnetic field is given by multi-scale expansion.It is verified by numerical simulation.It is shown that resonant heating can be produced by electrostatic wave with sub-harmonic frequency of the cyclotron.Moreover,it is shown that the heating efficiency does not increase with the amplitude of driving wave even if for the same frequency,which means there is an optimum combination of frequency and amplitude to get efficient heating.