An object state determining apparatus comprising: a first light source, configured to generate first light in a first direction, wherein first reflected light is generated while the first light is emitted to an object; a second light source, configured to generate second light in a second direction, wherein second reflected light is generated while the second light is emitted to the object; at least one light sensor, configured to sense a first light amount of the first reflected light and a second light amount of the second reflected light; and a determining unit, configured to determine a state of the object based on the first light amount and the second light amount. The object state determining apparatus can be easily fixed to an object to be detected and can efficiently detect the state of the object.