The static equilibrium equation of functionally graded circular plate was established by using elastic theory, and the neutral plane site of functionally graded elliptical plate was determined. On the basis, the nonlinear vibration and buckling differential equations for the functionally graded elliptical plate in uniform temperature field were derived, the approximate solution to nonlinear thermal vibration and buckling of functionally graded circular plate was obtained, and the effect of neutral plane site, gradient index and temperature on nonlinear thermal vibration and buckling of functionally graded elliptical plate was discussed and analyzed. The calculation results agreed well with the results, which verified the method. Analysis of examples indicates that the neutral plane site has certain influence on nonlinear thermal vibration and buckling of functionally graded elliptical plate in uniform temperature field.