Abstract: As each country has its own frequency allocation for radio frequency identification (RFID) in the ultra-high frequency (UHF) band and the development requirements in the global tracking of supply chain management, RFID broadband tag antenna has become a research focus. In this paper, a novel broadband patch antenna across the entire UHF RFID band is presented, by etching slots on the patch to broadben the operating bandwidth, with small size of only 33mm × 25mm ×1.6mm. The sturcture of the proposed antenna is simple without any via-hole or shorting plate. The theoretical detection distance of the antenna can reach 7.58m. The impedance match between the antenna and the tag chip can be tuned conveniently by changing the sizes of the slots. This new tag antenna has advantages of compact size and long readable range over some other broadband tag antennas. The measured curve of the input impedance is basically the same as the simulated. However, because the test condition is limited, the measured curve offsets about 200MHz to the lower frequency and the values have a certain degree of attenuation, compared with the simulated values.