eng Science and Education Publishing International Journal of Partial Differential Equations and Applications 2376-9556 2017-08-11 5 1 26 32 10.12691/ijpdea-5-1-4 IJPDEA2017514 article S. Kutluay 1 N. M. Yagmurlu murat.yagmurlu@inonu.edu.tr 1 Department of Mathematics, Faculty of Arts and Sciences, İnönü University, Malatya, Turkey In this paper, the bi-quintic B-spline base functions are modified on a general 2-dimensional problem and then they are applied to two-dimensional Diffusion problem in order to obtain its numerical solutions. The computed results are compared with the results given in the literature. http://pubs.sciepub.com/ijpdea/5/1/4/ijpdea-5-1-4.pdf Galerkin Finite Element Method Bi-quintic B-splines Two-dimensional B-splines Modified bi-quintic B-splines Two-dimensional Diffusion Equation