Disclosed is an angle sensor, including a gear structure (1), an eddy current probe (2) and a processing unit (3), wherein the gear structure (1) is a gear mounted and fixed on the outer circumference of a rotating shaft or a gear formed by machining on the outer circumference of the rotating shaft, and a positioning structure (P) for feature angle recognition is provided on an outer circumferential side of the gear structure (1); the eddy current probe (2) is positioned at the outer circumferential side of the gear structure (1), and the eddy current probe (2) faces a gear tooth and a tooth groove of the gear; and the processing unit (3) is connected to the eddy current probe (2) and is used for processing signals and outputting an angle measurement signal. Also disclosed is an angle measurement method.