The College of Science in the Department of Mathematics discussed a Ph.D. thesis titled Finite element analysis of some nonlinear partial differential equations with Neumann boundary conditions  for postgraduate student Ghufran Adel. In this thesis, Mathematical and numerical analysis has been conducted on two systems of reaction-diffusion equations. Initially, we examine two variations of Cahn-Hilliard equations, studied within open bounded convex domains DC Rd (where d = 1,2,3), sub- ject to Neumann boundary conditions.