This paper would treat with the question of homeomorphism of nonIinear monotone operataros

which is not necessarily Frechet differentiab. le. By using inversion theorems

We can fina a new Simpler proof to F.E.Browder`s theorem [3] proved in Hilbert spaces and extend it to reflexive Banach Spaces; and thns improve a existence and uniquness theorem [4] of the solutions for nonlinear equetions. Finally

an example would be given to demostrate the applications of these the- orems to boundary value problems for Semilinear elliptic equations.