The invention relates to a small-diameter sleeve window sidetrack drilling traction type well fixing method, and belongs to the technical field of petroleum and gas well fixing. According to the technical scheme of the small-diameter sleeve window sidetrack drilling traction type well fixing method, a smart short-circuit circulating short joint along with a well fixing pipe column enters a well together; an original well drilling liquid is injected, an annulus is washed, then a special-amount conventional extra-low density well drilling fluid (or branch water), a separating liquid, cement paste and the original well drilling liquid are injected in sequence; a short-circuit circulating channel is opened, and the conventional extra-low density well drilling fluid (orbranch water) enters the annulus; and after the conventional extra-low density well drilling fluid (or branch water) fully passes, the short-circuit circulating channel is closed; the cement paste is pressed into the annulus by using the pressure difference, and the traction type well fixing is formed. The small-diameter sleeve window sidetrack drilling traction type well fixing method has the advantages that by reducing the annulus liquid density, the total pressure borne by the well bottom is reduced, pressing crack of the well bottom is prevented, the one-time success rate of small-diameter sleeve window sidetrack drilling well fixing is greatly improved, the well fixing quality is ensured, the cost is reduced, and pollution of an oil-gas layer is avoided.