A detection method for a capacitive touch device is provided. The detection method includes steps of: driving an Mth driving line among an m driving lines of the capacitive touch device, wherein M is a natural number smaller than or equal to m and greater than 1; selecting a plurality of sensing lines among n sensing lines; obtaining a plurality of sensing values by detecting voltage changes at the selected sensing lines; determining whether to perform a noise reduction operation on the sensing values; if yes, calculating respective differences between the sensing values and a baseline value, and generating a noise correction value corresponding to the sensing values by performing a statistical computation on the differences; and correcting the differences according to the noise correction value.