Frequency tuning characteristics of the multi-layered micro-resonators have been extensively investigated by using thermal and piezoelectric actuations. Based on the layerwise displacement theory and geometric nonlinear formulation, the nonlinear deformation and its attendant vibration characteristics of un-symmetrically deposited camped-camped micro-beams under piezoelectric and thermal actuations have been analyzed. The effects of the eccentric piezoelectric actuation and uniform thermal loading on the large deflection and natural modes were discussed with respect to geometric nonlinear responses and initial imperfection. Present results show that both piezoelectric and thermal actuations can effectively tune the resonant frequencies as increasing and decreasing desired values by the alternative selection of the dominance between in-plane deformation and out-of-plane deformation.