Theoretical investigation is performed to discuss the heat and mass transfer behavior of chemically reacting magnetohydrodynamic Casson and Maxwell fluids past a stretching sheet with Brownian moment and thermophoresis effects with internal heat source/sink. Runge-Kutta based shooting procedure is employed to yield the solutions of the problem. Effects of the pertinent parameters on velocity, thermal and concentration boundary layers are analyzed through graphical illustrations. Also computed the reduced Nusselt and Sherwood numbers and presented through tables. It is found that the boundary layers of temperature and concentration fields are non-uniform for Casson and Maxwell fluids. Thermal and concentration fields of Maxwell fluid is highly influenced by the pertinent parameters when compared with the Casson fluid. © 2017 Faculty of Engineering, Alexandria University