The invention relates to a fire protection device (10) for a starter-controller device (2) of an electrical installation, the starter-controller device (2) comprising at least one connection terminal, each connection terminal being adapted to be connected to an electrical conductor, the protection device (10) comprising thermal monitoring means for the or each electrical conductor adapted to detect a temperature increase, at each connection terminal, above a predetermined threshold. This protection device is suitable for being mechanically fastened to the starter-controller device (2) via at least one mechanical connection member (16). The thermal monitoring means comprise at least one temperature sensor (36a, 36b, 36c) able to sense a temperature in a first hollow housing (8a, 8b, 8c) of the starter-controller device (2) situated near a connection terminal of a conductor. This protection device further includes an injection device (30), electrically connected to said at least one temperature sensor (36a, 36b, 36c), adapted to inject a fire extinguishing agent toward the first hollow housing(s) (8a, 8b, 8c) once the temperature sensor (36a, 36b, 36c) has detected a temperature above the predetermined threshold.