The invention relates to a technique for refining fiber, especially providing a drawing refining method of jute. Wherein, it sprays spray agent to jute fiber for maintenance, while said agent contains alkyl sodium and ethylene oxide condensate, whose penetrability can penetrate the effective component of agent into fiber and expansion function can expand the inner structure of fiber; the adhesive between fibers are relaxed too, to show expansion effect; the agent contains anode ion modified organic silicon softening agent to realize soften function; it can realize drawing function in yarn processing, to displace fibers to refine them. The invention can solve the problems of present technique which will shorten the length of jute fiber when refines fiber, and the processed jute fiber has worse weave property. The invention uses agent to maintain fiber, and displace the fiber of yarn via the drawing function in said processes to realize refining effect.