The invention relates to a seamless steel tube for a rare-earth-containing L625Q submerged pipeline and a production method of the seamless steel tube. The production method comprises the following steps: carrying out pretreatment on blast furnace molten iron so that the S content of the blast furnace molten iron is reduced to below 0.010% in percentage by mass; adding the treated blast furnace molten iron and steel scrap to a top-bottom combined blowing converter for smelting, adopting deoxidation alloy in the steel tapping process for deoxidation alloying, carrying out final deoxidation by adopting an aluminum deoxidation technology, carrying out slag blocking or deslagging in the steel tapping process, adding lime blocks after adding the alloy in the steel tapping process, then adding the smelted molten iron to an LF (Ladle Furnace) for refining, blowing argon during refining, and heating for warming in a manner of gradually increasing the warming speed; then carrying out slag making, desulfurization, composition adjustment and warming operations; adopting the operation of white slag making, and adding ferrovanadium alloy and ferrotitanium alloy; finally continuously blowing argon gas softly at the bottom, adding rare earth wires, and then carrying out VD (Vacuum Distillation) vacuum treatment, round billet continuous casting, tube blank heating, perforating, continuous rolling, sizing, cooling, saw cutting, heat treatment, straightening, flaw detection and chamfering.