The invention discloses a method and device for detecting an elevation or water depth based on a mobile terminal screen, wherein the method comprises the following steps of: acquiring a current external pressure value and current environmental information which act on the mobile terminal screen; judging detected data types according to the current environmental information, wherein the detection data types comprise the elevation and the water depth; calculating a pressure difference value according to the current external pressure value and the sea level atmospheric pressure value; according to the detected data types, calling a corresponding algorithm, substituting the pressure difference value to obtain the elevation value or water depth value where the mobile terminal screen is currently located. According to the invention, the pressure value acting on the screen is detected by using a press type mobile phone, the characteristic of the external environment are acquired through a camera, so that the type of the data to be detected can be automatically judged, the value of the elevation or water depth can be calculated conveniently and quickly.