A liquid output sensing device includes a body, a sensing unit, a first optical fiber, and a second optical fiber. The body is connected with a delivery structure. A liquid input port is disposed on one end of the delivery structure, and a liquid output port is disposed on another end of the delivery structure. A liquid delivery channel is disposed between the liquid input port and the liquid output port. The liquid delivery channel is connected with a first controller. The sensing unit is connected with the body, and is electrically connected with the first controller. One end of the first optical fiber is connected with the sensing unit. Another end of the first optical fiber and one end of the second optical fiber are connected with the delivery structure and near the liquid output port. Another end of the second optical fiber is connected with the sensing unit.