Understanding influence of surface texturing on frictional behavior is one of great importance for industrial applications.However, effects of surface texturing on friction are not fully understood.To clarify this, we investigated the effects of dimple width (10 μm dimple, 20 μm dimple, 48 μm dimple and 110 μm dimple) and groove direction (parallel groove and vertical groove) on oil film thickness and friction coefficient using a laboratory-built tribometer with in-situ film thickness observation. As a results, 10 μm dimple showed lowest friction and highest film thickness in all texture surface. In addition, the effects of groove direction influence the friction coefficient but hardly do film thickness. We considered that the mechanism of the frictional property improvement by surface texturing was the increase of film thickness and decrease the edge contact between texture groove and disk surface.