The invention discloses a movable line physical isolation protection construction method for maintaining operated railway lines. The method includes the steps: selecting and implementing multi-group continuous pile foundation unit construction operations between an upper line and a lower line; sequentially arranging multi-group continuous pile foundation units at the middle position between a ballast-less rail upper line and a ballast-less rail lower line along the traveling direction parallel to the upper line and the lower line; sequentially mounting a pile foundation, a base sliding way anda slider from top to bottom when each pile foundation unit is built; sequentially and fixedly connecting the bottoms of a plurality of H-shaped steel vertical columns on the sliders corresponding tothe multi-group pile foundation units; correspondingly inserting two sides of a unit plate into two sliding grooves in two adjacent H-shaped vertical columns between two adjacent pile foundation units. According to the method, the influence on normal driving is avoided when margin requirements are met, and the method further has the technical advantages that structure design is reasonable, use performances are stable and reliable, construction is remarkably accelerated and the like.