In this article, a fourth order quintic spline method has been developed to obtain numerical solutions for second order boundary value problems with Dirichlet boundary conditions. The developments of the quintic spline method and convergence analysis were presented. Three test problems have been considered for comparison purposes. The numerical results showed that the quintic spline method is more accurate compared to existing cubic spline method when solving nonlinear second order boundary value problems but vice versa when solving linear second order boundary value problems.