The utility model relates to a cabinet control by temperature change trouble alarm device of transformer substation, it is including the singlechip, presupposition voltage in the singlechip, the electric current, the temperature, and light source alarm parameters, it has photosensitive sensor and temperature sensor to connect in parallel at the monolithic machine side, wherein photosensitive sensor installs at the box door reveal, temperature sensor installs and inclines at heating device, it is used for detecting electric current between temperature controller and the heating device still to connect in parallel to have at the monolithic machine side, the current detection circuit and the voltage detection circuit of voltage, current detection circuit passes through current transformer and inserts between temperature controller and heating device circuit, voltage detection circuit directly inserts between temperature controller and heating device circuit through the wire. This application does not change former heating device's mode of connection, need not lay the signal and upload the circuit, can be directly with the transformer substation in the temperature controller link to each other, detect voltage, the electric current of temperature controller, monitor switch, the temperature of box, the condition such as leak simultaneously, made things convenient for the daily detection of maintainer.