A touch detection method, suitable for a touch display panel including multiple sensing pads, is disclosed. The sensing pads are divided into groups and each of the groups includes at least two columns of the sensing pads. The touch detection method includes following steps. In a first mode, the sensing pads are scanned group-by-group for detecting whether a touch event occurs on a touch identified group. In a second mode, the sensing pads are scanned column-by-column to identify a touch position of the touch event.