The impedance matching and radiation performance of the RFID tag antenna will be affected in the metal environment. Meanwhile, in order to reduce the thickness of the tag, a miniaturized low-profile double-arm spiral anti-metal UHF RFID tag is proposed. The tag antenna is composed of an upper radiating patch and a lower ground patch. The structure of the upper radiating patch is that two dipole arms spirally extend outward from the center, presenting a central symmetry, and the chip is located at the symmetrical center of the two spiral arms. A metal short-circuit arm is introduced from the dipole arm of the upper radiation patch to connect the lower layer to the ground. By changing the width of the dipole arm and the position of the short-circuit arm in the radiation patch, the resonant frequency of the tag antenna can be effectively adjusted and the size of the antenna can be reduced. The size of the tag antenna proposed in this paper is 27 mm×0.6 mm. The tag is attached to the upper surface of the metal cylindrical water valve. Under the condition of an equivalent omnidirectional radiation power of 3.28 W, the measured reading distance around one circle in the horizontal direction is 8.5~9.3 m. The tag antenna designed in this paper features low profile, metal resistance, omnidirectionality, long reading distance and easy production. It is suitable for cylindrical metal application scenarios such as metal water valves and metal bottle caps for alcoholic beverages, and is managed in aspects such as production transportation, identification and monitoring using RFID technology.