This paper presents the relative evaluation methods on slipperiness of stairway treads from a viewpoint of safety of the aged. First, sensory tests with the aged (upper 60 years old) and young persons (20 to 59 years old) were carried out, to make evaluation scales of slipperiness. Next, it was cleared that C. S. R・S which was the physical value of slipperiness of stairway treads made in the past studies corresponded to each evaluation scale, also the correspondence was enough as the evaluation indexes. Finally, the evaluation indexes and the measuring method of C. S. R・S were presented as relative evaluation methods.