Research on the increasingly significant issue of fatigue failure in pedestrian structures due to crowd-induced vibrations is limited. This paper uses a steel-glass footbridge as a test platform to study the fatigue performance of the footbridge before and after the installation of a Tuned Mass Damper （TMD）. The APS400 electronic shaker is used to simulate pedestrian load， and longterm strain monitoring data is analyzed to determine the fatigue stress spectrum and daily average damage degree of the structure， which is then used to estimate its fatigue life. The results show that the installation of the TMD reduced the peak acceleration at half of the structure from 0.15 m/s2 to 0.084 m/s2， a vibration reduction rate of 44.0%. The peak displacement was reduced from 2.98 mm to 0.92 mm， a vibration reduction rate of 69.1%； and the strain amplitude was reduced from 40 to 13， a vibration reduc? tion rate of 67.5%. The amplitude of the equivalent effect force across the middle of the structure is the largest， and the fatigue life is the shortest， at 74 years. After the installation of the TMD， the fatigue life of the structure span increased to 2880 years， nearly 39 times longer， and the fatigue life at other measurement points extended by 3.95 times and 7.41 times.