Disclosed is a three-dimensional gesture sensing method. The three-dimensional gesture sensing method comprises the following steps. Step A: driving at least one first conductive line of conductive lines in the touch sensing device as a first working sensing line, and driving at least one second conductive line of the conductive lines in the touch sensing device as a second working sensing line, such that a sensing area is formed between the first working sensing line and the second working sensing line. Step B: detecting a conductor according to the sensing area. Step C: dynamically adjusting at least the area, the position or the amount of the sensing area according to the conductor to implement a three-dimensional gesture sensing.