The invention discloses a screen unlocking method and a screen mounting system. Through calculation, a reference point is taken as a peak, and that whether unlocking is performed or not is judged according to the size of an angle between the starting position and the current position of the touch point on a screen. Due to the adoption of the technical scheme, the unlocking path and the target location of unlocking are not limited, the operation is more casual, and user experience feeling is also enhanced; and meanwhile, due to the simple arrangement, the use is more convenient and error unlocking is prevented.