The invention discloses a production method of rack steel for a self-elevating oil extraction platform, and belongs to the field of metal materials. At least two continuous casting sheet billets are used as raw material. The continuous casting sheet billets are welded into billets with large thickness by combining gas shielded welding, submerged arc welding, and vacuum electron beam welding or full-vacuum electron beam welding. The billets with large thickness are heated in a bogie-type furnace or a soaking furnace. The heated billets are rolled through a heavy plate mill, water-cooled, and heat treated to obtain the rack steel for the self-elevating oil extraction platform. The rack steel produced by the method is fine in steel plate comprehensive mechanical performance, high in operability, low in cost, and high in production efficiency.