A fingerprint identification sensor, a fingerprint identification method and an electronic device are disclosed. The fingerprint identification sensor includes a substrate; a fingerprint sensing element disposed on the substrate and including a thin film transistor, an off-state leakage current of the thin film transistor varying with the intensity of light irradiating onto an active area thereof; and a fingerprint identification light source arranged to emit light that irradiates onto a finger and is reflected thereby, the reflected light irradiating onto the active area of the thin film transistor. Thus, the fingerprint identification can be realized conveniently, and the fingerprint identification sensor has at least one of the advantages like high sensitivity and simple structure.