This article reports an analytical solution for steady natural convection in a slender rectangular porous cavity with hydrodynamic, thermal, and solute anisotropy, and uniform flux of heat and mass on the vertical sides. The principal directions of the permeability, thermal dijfusivity, and solute diffusivity tensors are taken independently oblique to the gravity vector. The assumptions inherent in the derivation of the analytical solution are validated by comparison with numerical solutions. The analytical solution is shown to be valid for aspect ratio beyond 3. A limited parametric analysis is also performed. The effect of the anisotropic parameters (K*, αØ, DØ, θ1, θ2, and θ3) are seen to be marked. Copyright © 2000 by Begell House, Inc.