Summary: In this paper, the iteration perturbation method proposed by J.H. He
[Non-perturbative methods for strongly nonlinear problems, Dissertation.de-Verlag im Internet GmbH (2006); Chaos Solitons Fractals 26, No. 3, 827–833 (2005; Zbl 1093.34520
)] is used to generate periodic solutions of van der Pol oscillator with a forcing term, forcing oscillator with quadratic type damping and van der Pol oscillator with excitation term. The comparison of the obtained results verifies its convenience and effectiveness.