An experimental investigation is carried out for natural-convection heat transfer to air from an array of five cylinders which are arranged in an inclined plane. The heat transfer coefficient of each cylinder in the array and the average heat transfer coefficient of the array are obtained for a variety of combinations of cylinder spacing, cylinder surface temperature and array inclination angle. A correlation equation for the average heat transfer coefficient of the vertical array is proposed. A method for estimating the heat transfer coefficient of each cylinder in the array is also given. Application of these results and the previously proposed heat transfer correlations for the horizontal array shows good agreement with the heat transfer coefficient of each cylinder in the inclined array.