A double-layer beam warper, comprising machine head, left wallboard of machine head, electromotor, middle wallboard, tail wallboard, servo-actuator, ball screw, contains connecting rod mechanism, double layer roll mechanism and synchro actuating mechanism. Connecting rod mechanism is firmly joined to tail wallboard. Servo-actuator through ball screw and connecting rod mechanism drive upper and lower guide needle bars, arranged in parallel, whose swing are equal and swing direction are inverse, move to and fro in horizontal direction respectively. Upper and lower 0 roll, set among left wallboard of machine head, middle wallboard, tail wallboard, is driven by electromotor run-in synchronism and upper and lower beam rotate synchronously by friction force of upper and lower roll. Because of uniform diameter and rotational speed of upper and lower roll, linear speed of upper and lower beam are stationary so as to ensure beaming of high efficiency and quality. The invention is characterized in simple structure, convenience adjusting, stationary performance and energy conservation.