A system and method for detecting the performance of a bi-polarized antenna including two antennas in a wireless communication system is provided. The system may include at least one directional coupler connected to the bi-polarized antenna configured to couple a transmitting signal of the first antenna and another signal from the bi-polarized antenna; a power detector connected to the at least one directional coupler and configured to measure the power of the transmitting signal and the another signal as analog results, respectively; an analog-digital converter connected to the power detector and configured to convert the analog results into digital results; and a processing unit connected to the analog-digital converter and configured to calculate the difference of the digital results. The performance of the bi-polarized antenna can be accessed by the above-measured polarization isolation.