In this paper, we have presented our circular polarization antenna for the RFID system, which was presented by us. The focus of this contribution is on analyzing and comparing the antenna performance for the 900MHz RFID application. As a result of performance test of the antenna designed, it was found that return loss (S11) was about -41.633dB at 914MHz, which was relatively small, and antenna gain was about 5.69 ~ 9.59dBi. And it was confirmed that 50Ω impedance matching was about 49.20Ω and it can be applied for every RFID system. Therefore, the antenna was designed to have higher gain of circular polarization antenna by improving the reception which is one of the most important parameters of the RFID reader, which is expected to be extensively used to recognize multi-tag in the distance.