[Object] To provide a signal transmission device and management system which are capable of transmitting a signal including information of an attachment target or information of the surrounding of an attachment target.[Solution] A management system includes: a signal transmission device which includes a housing that is attached to an object to be managed in a predetermined direction, a first optical power generation unit and a second optical power generation unit that have light receiving units on a first surface and a second surface facing outwardly in a predetermined direction, respectively, a first temperature sensor and a second temperature sensor that have thermal contacts on the first surface and the second surface, respectively, a communication control unit for transmitting a signal including temperature information detected by the first temperature sensor and the second temperature sensor using power generated by at least one of the first optical power generation unit and the second optical power generation unit； and an information processing device which has a control unit for receiving a signal transmitted from the signal transmission device and outputting the state information of an object to be managed to which the signal transmission device is attached on the basis of the temperature information detected by at least the first temperature sensor and the second temperature sensor.
