This paper examines theoretical study of effect of magnetic field on infinitely short rough porous journal bearing with the heterogeneous slip/ no-slip surface. Using Christensen stochastic model, Reynolds equation for uni-directional longitudinal roughness pattern is derived. The expressions for pressure and load carrying capacity are obtained as a function of various parameters like Hartmann number, roughness parameter, slip parameter, permeability parameter. It is observed that inclusion of roughness effect and Hartmann number boosts the load carrying capacity.