Large-span urban arch bridges often adopt non-load-carrying auxiliary cables to enhance the aesthetic performance of the structure. Due to the relatively low level of cable tension, these auxiliary cables are susceptible to adverse vortex-induced vibration responses under wind excitation, leading to fatigue fracture at the cable anchorage ends. This paper investigates the fatigue performance of auxiliary stay cable anchorage ends under vortex excited vibrations in a tied-arch bridges. Firstly, a joint probability density model of wind speed and wind direction is established based on a two-dimensional Copula function. A finite element analysis model of the cable-anchorage end is developed. Furthermore, the stress distribution at the anchorage end under vortex-induced resonance excitation of the cable is investigated. An evaluation method for the fatigue performance of the anchorage end considering the effects of wind speed and wind direction is proposed, and the time-varying behavior of the fatigue reliability index of the auxiliary stay cable is analyzed. The results indicate that, under the influence of vortex-induced forces caused by natural winds, significant out-of-plane stresses are induced at the anchorage end, leading to a decrease in the fatigue reliability index of the auxiliary stay cable to the target level within 8 years.