PURPOSE: To make it unnecessary to reset various modes on the master equipment side by inhibiting the restoration of a previously determined mode out of plural setting modes set up by an operation switch when the master equipment receives a restoration signal from a receiver.

CONSTITUTION: The radio type alarm system is provided with plural slave equipments 12-1 to 12-n each of which is connected to a sensor 10 for detecting abnormality such as a fire and transmits an abnormality detecting signal including address information when the sensor detects the abnormality and plural master station 14-1 to 14-3 each of which receives transmission signal from one of the slave equipments 12-1 to 12-n, informs the abnormal state and sends the received information to a receiver 16 through a transmission line. After the time of depressing a restoration switch 18, the receiver 16 sends a restoration signal to the master equipments 14-1 to 14-3 and resets various modes set up by the operational switches 20, 22. At the time of receiving the restoration signal from the receiver 16, each of the master equipments 14-1 to 14-3 inhibits the restoration of the previously determined mode out of plural setting modes set up by the operation switches 20, 22.