The problem of laminar mixed convection from an isothermal cylinder with highly conductive fins in cross flow was solved numerically. The average Nusselt number was calculated at different combinations of number of fins (0-17), fin height (0-2), Reynolds number (10-200), and buoyancy parameter (0-5). The fins were most effective at low Reynolds numbers and low buoyancy. The addition of short fins at high values of the Reynolds number and buoyancy parameter resulted in a slight reduction in the Nusselt number. There was an optimal number of fins beyond which additional fins did not increase or even reduce the average Nusselt number. This number was Reynolds number- and buoyancy parameter-dependent. When using a small number of long fins at low buoyancy, an even number of fins was better than an odd number of fins.