Frictional behaviors of Nylons having different chemical structures were followed by observing the change of frictional coefficient in the glassy, transition and melt-flow regions of the system.In the glassy region, a constant value of frictional coefficient was observed in spite of the variation in contact pressure. Only shearing fracture was observed in the region.A good correlation was observed between the frictional coefficient and shearing modulus of elasticity or hardness of Nylons.In the transition region, the maximum value of frictional coefficient was observed at Tg and Tm. Stick and slip behavior was also observed in the region.A good correlation was observed between the maximum values of frictional coefficient and damping. Orientation of Nylon layer was also observed in the region.