Abstract: In the present paper, we investigate the effects of heat source and radiation on unsteady magneto hydrodynamic free convection flow past an infinite heated vertical plate in a porous medium. The dimensionless governing equations are solved numerically using finite element method. Numerical evaluatation of the analytical results are carried out for different values of dimensionless parameters. The results are presented graphically for velocity, temperature and concentration profiles, and observed that, when the heat source and radiation parameter increases, the velocity and temperature decrease in the velocity.