In this paper, the joule heating and magnetic field effects on the mixed convection two-dimensional boundary layer flow of a micropolar fluid near the stagnation point over a stretching vertical sheet in the presence of heat generation have been obtained and studied numerically. The governing continuity, momentum and energy equations are converted into a system of non-linear ordinary differential equations by means of similarity transformation. The resulting system of coupled non-linear ordinary differential equations is solved numerically. Numerical results were presented for velocity, temperature and microrotation profiles for different parameters of the problem as material parameter, buoyancy parameter, magnetic field parameter, stretching parameter, Prandtl parameter, viscous dissipation parameter , Joule heating parameter, heat source parameter and other . Also the effects of the pertinent parameters on the skin friction, the rate of heat and mass transfer are obtained and discussed numerically and illustrated graphically