A multifunctional automobile alarm lamp includes an LED lighting device, a lamp housing, a rod mounting base and a lighting control device. The LED lighting device is installed in the lamp housing; the rod mounting base includes a connecting rod, a connecting board and a fixing bracket; the connecting board is for connecting the lamp housing; the connecting rod is for connecting the connecting board; the connecting rod is connected to the fixing bracket by a sliding sleeve method; the fixing bracket is installed to the top of the police car at where the alarm lamp is situated; the lighting control device is connected to the LED lighting device for controlling the lighting method of the LED lighting device. The present invention can expand the application functions of the LED alarm lamp.