The problem deals with the investigation of flow, heat and mass transfer behavior of Casson fluid in a squareacavity filled with a porousamatrix under the influence of thermal radiation. The flow problem's governing equations are non-linear partial differential equations that are converted into finite element equations and solved using the PenaltyaFiniteaElement method. A heating source partially heated the square porous cavity from below and symmetrically cooled it from both side walls. The effects of fluid yield stress on heat, mass and fluid transport inside the cavity are investigated for various values of temperature difference, across hot and cold surfaces. All significant findings have been expressed in terms of streamlines, isotherms, isoconcentration lines and avg Nusselt number, avg Sherwood number.