A door lock includes a panel, a base plate, and a middle plate. A handle and a thumb-turn are rotatably mounted on the panel, wherein the thumb-turn has a first spindle mounted on the middle plate and engaged with the thumb-turn, an upper cam mounted on a rear end of the first spindle. The handle has a second spindle mounted on the middle plate and engaged with the handle, and a lower cam with two shoulders mounted on a rear end of the second spindle. A linking sheet is provided between the middle plate and the base plate and has two legs each having a foot pushed by the respective shoulder and an upper end pushing the upper cam. Two slots are defined in the legs, and two springs are received in the longitudinal slots and are pressed between first stops and second stops.