The utility model discloses a bottom structure of a shallow-water pipe-laying ship. The bottom structure of the shallow-water pipe-laying ship comprises an outer bottom plate of the ship bottom and N grooves formed in the outer bottom plate of the ship bottom, wherein each of the N grooves is internally provided with a limber hole; N is an integer not less than 4. After the shallow-water pipe-laying ship is bottom-sitting, pressurization can be carried out by beating water in a region between the bottom structure and a seabed, the bottom of the shallow-water pipe-laying ship is broken away from the seabed, floating force provided by seawater is recovered, and a normal floating state is recovered.