Influence of thermal radiation on nanofluid heat transfer in existence of Lorentz forces is investigated. Viscosity of Fe3O4 ferrofluid is considered as a function of magnetic field. CVFEM is selected to solve this problem. Effects of radiation parameter (Rd), inclination angle (xi), Fe(3)O(4)water volume fraction (phi), Hartmann (Ha) and Rayleigh (Ra) numbers are demonstrated graphically. A correlation for average Nusselt number is extracted. Results demonstrate that rate of heat transfer enhances with augment of inclination angle. Nusselt number augments with rise of buoyancy forces and radiation parameter but it reduces with rise of Hartmann number. (C) 2017 Elsevier Ltd. All rights reserved.