PURPOSE: To provide a car audio security system which secures the perfection of security and is simple in operation.

CONSTITUTION: A remote commander 120 has an operating button section 121 to generate operating command, a transmitting section 122 to transmit the operating command, a memory section 123 to store an identification code, and a security releasing switch 124 to transmit the identification code to the transmitting section 122, and a car audio system 110 has a receiving section 111 to receive the operating command and the identification code, an audio apparatus section 112, a power source 113, a main switch 114, and a memory section 115 to store a reference code being the same as the identification code, and moreover has a security control section 116 to turn on the main switch 114 in the case where it is judged whether the identification code is the same as the reference code or not, and when they are judged to be the same.