Abstract: A comprehensive evaluation on melt conveying capacity of triangle arrayed triple-screw extruder, line arrayed triple-screw extruder and twin-screw extruder was carried out through the experiment of silicone oil extrusion. Dimensionless groups and traditional parameters were both used to evaluate the pressure generation capacity and energy consumption of the three extruders. And the experiments also reflected the influence of screw speed and throughput on the conveying capacity of the extruders. The research showed the triangle arrayed triple-screw extruder has better melt conveying performance than the others. And the reliability of the dimensionless evaluation was also proved, it can be applied to more evaluation between varies kinds or sizes of extruders.