An object detection sensor configured to detect that a target object acts on to-be-detected rays between a plurality of elements or to detect to-be-detected rays from a target object to output a predetermined detection signal, the object detection sensor configured to output the predetermined detection signal toward an external object detection device existing outside the object detection sensor to detect the target object, the object detection sensor comprising: a sensing unit configured to detect that the target object acts on to-be-detected rays between a plurality of elements or to detect to-be-detected rays from the target object to output a sensing signal, a control unit configured to command output of the predetermined detection signal in response to input of the sensing signal, a sensor output unit configured to output the predetermined detection signal in response to the command, a test signal reception unit configured to receive a test signal from the external object detection device, and a test signal response unit configured to output a test response signal to the external object detection device in response to reception of the test signal, the object detection sensor further comprising: a learning mode transition input unit configured to start a learning mode, a test signal determination unit configured to determine a state of the test signal received by the test signal reception unit in the learning mode, a test signal estimation unit configured to estimate a characteristic of the test signal from the determined state of the test signal in the learning mode, and a test signal verification unit configured to verify whether the estimated characteristic of the test signal is included in the test signal received by the test signal reception unit in the learning mode. a sensing unit configured to detect that the target object acts on to-be-detected rays between a plurality of elements or to detect to-be-detected rays from the target object to output a sensing signal, a control unit configured to command output of the predetermined detection signal in response to input of the sensing signal, a sensor output unit configured to output the predetermined detection signal in response to the command, a test signal reception unit configured to receive a test signal from the external object detection device, and a test signal response unit configured to output a test response signal to the external object detection device in response to reception of the test signal, the object detection sensor further comprising: a learning mode transition input unit configured to start a learning mode, a test signal determination unit configured to determine a state of the test signal received by the test signal reception unit in the learning mode, a test signal estimation unit configured to estimate a characteristic of the test signal from the determined state of the test signal in the learning mode, and a test signal verification unit configured to verify whether the estimated characteristic of the test signal is included in the test signal received by the test signal reception unit in the learning mode. a learning mode transition input unit configured to start a learning mode, a test signal determination unit configured to determine a state of the test signal received by the test signal reception unit in the learning mode, a test signal estimation unit configured to estimate a characteristic of the test signal from the determined state of the test signal in the learning mode, and a test signal verification unit configured to verify whether the estimated characteristic of the test signal is included in the test signal received by the test signal reception unit in the learning mode.