A Bluetooth based security system utilized to provide ad-hoc security services to secured assets. Such a Bluetooth based security system comprises a secured device (SD) equipped with Bluetooth (BT) technology; a plurality of Bluetooth Access Points (BTAPs) located at designated points to establish a BT link with the secured device (SD); and a security server (SS) connected to all BTAPs and arranged to provide access control and security services for the secured device (SD), wherein the security server (SS) obtains attribute information of the secured device (SD), including an unique device identification (ID) and a last known location of the secured device (SD), activates a lock with the secured device (SD), and sends location information of a designated BTAP and an unlock code to the secured device (SD), via the designated BTAP.