This paper reports the relationships found between the surface roughness and wettability of some industrial minerals, namely, calcite, barite, talc and quartz. These minerals were ground in ball, rod and autogenous mills to produce samples for roughness and wettability tests. The surface roughness values of those minerals were determined on the pelleted surfaces of the ground powders by employing HB 103-Surtronic 31 surface roughness measuring instrument. The wettability characteristics (gamma(c)) of these minerals ground in these different mills were also determined by flotation technique using the EMDEE MicroFLOT agitator. The experimental results revealed that the degree of hydrophobicity of these minerals increase with decreasing surface roughness and the particles having rougher surfaces lead to higher wettability independently from the mill type employed. (C) 2004 Elsevier B.V. All rights reserved.