The compactly supported wavelet basis functions are introduced into the con
struction of interpolating function of traditional finite element method wh
en analyzing the problems with high gradient, and the traditional interpola
ting method is modified. The numerical stability of the new interpolating p
attern is discussed and the convergence of the new method is also discussed
by patch test analysis. The additional freedom of the new interpolating pa
ttern is eliminated by static condensation method. Finally, the wavelet fin
ite element formulations based on variational principles are put forward.