A sliding door for a metal wired pet cage includes a pair of torsional springs a rotary locking member a rotary lifting handle and a sliding-type door plate wherein sliding guide rails of the sliding door are configured longitudinally, wherein the lifting handle is hingedly fixed to an upper end of the sliding-type door plate, the pair of torsional springs are fixed on the metal wired pet cage and are connected with both ends of the locking member, and the torsional springs is configured to drive the locking member to prop against the lifting handle so that the sliding-type door plate is at a locking state. When the sliding type door plate needs to be opened, the lifting handle is rotated upwards so that the locking member is separated from the lifting handle, and the lifting handle drives the sliding-type door plate to move upwards along the sliding guide rails.