The heat transfer characteristics for natural convection about an isothermal vertical cylinder with surface mass transfer (blowing or suction) have been determined by analysis. The problem was formulated by applying the local nonsimilarity method, and solutions were obtained by a numerical scheme which employs integrated forms of the governing differential equations. Numerical solutions were carried out for a wide range of values of parameters which respectively characterize the transverse curvature of the cylinder and the magnitude and sign of the surface mass transfer. The Prandtl number was varied between 0.01 and 10. It was found that the local Nusselt numbers for a vertical cylinder are less sensitive to surface mass transfer than are those for a vertical plate. The sensitivity of both the cylinder and the plate Nusselt numbers to the mass transfer is diminished at low Prandtl numbers and increased at high Prandtl numbers.