The invention discloses a method for reducing bending of a seamless steel tube cold-rolled core rod. The method comprises the steps of material inspection, tool mold preparation, rolling preparation,rolling production and finished product inspection, continuous feeding, segmented positioning, sleeve compensation, counterweight containing, uniform rolling, one-by-one adding and two-end fixing areadopted, a front tube blank, a rear tube blank, a feeding chuck, a core rod chuck and an inlet chuck are adopted together to form a whole, through the containing of the core rod by the tube blank, thebending deformation faults of the slender core rod with the diameter 100 mm or below in rolling are eliminated from the source, on the basis of guaranteeing the rolling quality of the seamless steeltube, the field treatment consumption and the production cost are reduced, the labor intensity is reduced, and the consumption of the rolling mechanism and the tool mold of the rolling mechanism is reduced. The method is smooth and compact in working procedure, convenient to operate and maintain on site, safe, reliable, practical and efficient; the equipment investment is not increased, the cost is low, the expense is less, the on-site implementation is easy, the method has the advantages of eliminating the fault and reducing the cost and promoting the production effect, and the universality is strong.