Abstract: Wall slip behavior of melts of polypropylene, high-density polyethylene polystyrene and poly(methyl methacrylate), was studied by a double capillary rheometer, and effects of shear stress and temperature on wall slip velocity (vs), and wall slip on flow of the melts were investigated. The results indicated that a stick-slip transition was observed for the four polymer melts vs increased as a power function of shear stress, and the critical shear stress for the onset of stickslip transition decreased with an increase of temperature.It was also observed that the effect of wall slip on melt filling behaviors was relative to the type of polymers, which became more significant with the decrease of channel diameters