Methods and systems for ascertaining the roughness of a print media surface are described. In one embodiment, a print media roughness detection mechanism comprises a surface-engaging member that is configured to physically engage a print media surface. A reflective member is provided and is joined with the surface-engaging member. One or more light sources are provided in operable proximity to the reflective member and are configured to project light energy toward the reflective member. A position detector is mounted in operable proximity to the reflective member and is configured to receive light energy that is reflected from the reflective member. The surface-engaging member is configured for displacement by the print media's surface in accordance with variations in the roughness of the surface sufficiently so that light that is reflected by the reflective member and received by the position detector can be utilized to ascertain a measure of the print media's roughness. In one embodiment, the print media roughness detection mechanism is implemented in connection with a printing device such as a laser or ink jet printer, and print parameters can be manipulated in accordance with roughness measures that are provided by the detection mechanism.