Abstract: Polyamide 6(PA6)/ionic liquid composites were prepared by melt blending and extrusion. Effect of the content of the ionic liquid on rheological behaviors of the composites was investigated by melt flow indexer and capillary rheometer. The results indicated that the melt flow index of the composites was improved with increasing content of the ionic liquid. The apparent viscosity decreased with an increase of ionic liquid content and temperature, whereas the nonNewtonian index increased. Moreover, the viscous flow activation energy of the composites decreased with the increase of the ionic liquid contents. The structural viscosity index decreased with an increase of temperature at first and then trended to increase with increasing content of the ionic liquid.