An antenna assembly according to the present invention includes an antenna, a protecting device and cables. A radio frequency module is set before the antenna assembly and supplies signal power to the antenna through cables. The protecting device is located between the antenna and the radio frequency module so as to avoid undesired direct current to flow into the radio frequency module. The antenna, protecting device and radio frequency module are connected by cables. Connecting with and protected by the protecting device, the RF module works reliably under the above-mentioned construction of the antenna assembly which can hardly affect the performance of the antenna.