The invention provides a translational start-stop plane gate system for a ship lock, which comprises plane gates 1, translational start-stop devices 2, gate grooves 3 and common gate grooves 4, wherein each plane gate 1 is in a common plane gate structure, and consists of a panel 52, a plurality of horizontal main beams 49, a plurality of horizontal secondary beams 48, two edge columns 51 and a plurality of longitudinal beams 50; each translational start-stop device 2 can be self-walking, consists of a power source 5, a transmission shaft 7, elastic couplers 8, a driving wheel 9, a reducer 10, rollers 11, an underwater rail 12, gate limiting devices 13, an elastic anti-collision device 14 and a power source control system 15, and is fixedly mounted at the bottom of each gate 1; the power sources 5 transmit a torque to the driving wheels 9 through the transmission shafts 7, the couplers 8 and the reducers 10, so that the driving wheels 9 roll on the rails 12, the rollers 11 roll on the underwater rails 12 with the driving wheels 9 together, and the plane gates 1 are driven to move horizontally to achieve start and stop of gates; and start and stop motion of the gates is along horizontal straight lines of the rails.