The purpose of this study is to investigate the effects of shaft surface roughness, speed, seal inner diameter, and hp geometry on the rotary lip seal's performance. For this reason, a test system was developed. In this test system, a cylinder block is placed on four load cells to monitor the friction torque generated between seal and counter face. Radial hp geometry was taken as the prior criteria to group the seals for experiments. Two different profiles (with and without dust lip) and three different inner diameters (30-35-40 mm) were selected for the tests. Three shaft surface roughness values for each diameter were also tested. One shaft surface roughness value is between the limits that are recommended in standards, and two others are greater and less than that limits. At the end of the systematical experiments, variations of friction torque with respect to shaft surface roughness, lip profile and shaft diameter have been determined.