The invention discloses a lateral-sliding translation door which comprises a door frame, an auxiliary frame and a door leaf. Sliding grooves are symmetrically formed on two sides inside the door frame, the auxiliary frame is placed inside the door frame, T-shaped sliding grooves, sliders and a notch are arranged on the auxiliary frame, the T-shaped sliding grooves are symmetrically formed in the top and the bottom of the auxiliary frame, the sliders are fixedly mounted on two sides of the rear end outside the auxiliary frame and nested in the sliding grooves, the notch is formed on the left side of the front end of the auxiliary frame, the door leaf is placed inside the auxiliary frame, a door lock and square grooves are arranged on the door lock, the door lock is fixedly mounted on the left side of the door leaf through bolts, the square grooves are symmetrically formed above and below the right side of the door leaf, a siding plate is slidably connected inside each square groove, anda T-shaped shaft is mounted and fixed at the outer end of each sliding plate through screws and nested in a T-shaped sliding groove. The door is opened through lateral sliding, so that utilization rate of space in front of the door is increased.