The objective of this paper is to study the entropy generation and natural convection of water- Al2O3 nanofluid in an inclined cavity which consists of two connected inclined triangular enclosures under a horizontal magnetic field. The horizontal diameter of the cavity is small in thickness and has the temperature Tc. Half of the bottom wall and also the right wall are at the temperature Th. The rest of the walls are adiabatic. The governing equations of the nanofluid flow are algebrized and solved using the FVFEM method. The effective parameters are 103
