A window blind, comprising: a headrail; a bottom rail; a plurality of slats suspended between the headrail and the bottom rail through a ladder tape, wherein the bottom rail is adapted to be operated by a lifting cord to move between a high position and a low position, whereby to collect or expand the window blind; an input mechanism adapted to change a location of the bottom rail; an adjustment output mechanism provided in the headrail, wherein the adjustment output mechanism is adapted to be operated with the input mechanism simultaneously; an adjusting shaft, of which an end is connected to the adjustment output mechanism, wherein the adjustment output mechanism is adapted to be driven by the input mechanism to rotate the adjusting shaft, whereby to make two warps of the ladder tape have relative movement in a vertical direction, tilting the slats between a first position and a second position; and a lifting shaft adapted to be driven by the input mechanism, wherein, when the lifting shaft is continuously driven by the input mechanism to roll up the lifting cord, and the lifting cord moves the bottom rail toward the high position, the slats are located at the second position; when the lifting shaft is continuously driven by the input mechanism to release the lifting cord, and the lifting cord moves the bottom rail toward the low position, the slats are located at the first position, characterized in that the input mechanism comprises a transmission member, and the transmission member is adapted to be operated to rotate in a first rotation direction or a second rotation direction opposite to the first rotation direction; the adjustment output mechanism comprises an adjustment output wheel and an adjustment driven wheel, wherein the adjustment output wheel is adapted to be rotated along with the transmission member, and to drive the adjustment driven wheel to rotate; the adjustment driven wheel is adapted to drive the adjusting shaft to rotate. a headrail; a bottom rail; a plurality of slats suspended between the headrail and the bottom rail through a ladder tape, wherein the bottom rail is adapted to be operated by a lifting cord to move between a high position and a low position, whereby to collect or expand the window blind; an input mechanism adapted to change a location of the bottom rail; an adjustment output mechanism provided in the headrail, wherein the adjustment output mechanism is adapted to be operated with the input mechanism simultaneously; an adjusting shaft, of which an end is connected to the adjustment output mechanism, wherein the adjustment output mechanism is adapted to be driven by the input mechanism to rotate the adjusting shaft, whereby to make two warps of the ladder tape have relative movement in a vertical direction, tilting the slats between a first position and a second position; and a lifting shaft adapted to be driven by the input mechanism, wherein, when the lifting shaft is continuously driven by the input mechanism to roll up the lifting cord, and the lifting cord moves the bottom rail toward the high position, the slats are located at the second position; when the lifting shaft is continuously driven by the input mechanism to release the lifting cord, and the lifting cord moves the bottom rail toward the low position, the slats are located at the first position, characterized in that the input mechanism comprises a transmission member, and the transmission member is adapted to be operated to rotate in a first rotation direction or a second rotation direction opposite to the first rotation direction; the adjustment output mechanism comprises an adjustment output wheel and an adjustment driven wheel, wherein the adjustment output wheel is adapted to be rotated along with the transmission member, and to drive the adjustment driven wheel to rotate; the adjustment driven wheel is adapted to drive the adjusting shaft to rotate.