In order to explore the loading situation of bracing tube sealing plate of quayside container crane and the fatigue life of dangerous weld position, the typical load conditions of 65 t/60 m quayside container crane are analyzed. The fatigue load amplitude of upper horizontal bracing tube bracing of door frame is calculated, the loading situation of bracing tube sealing plate weld is studied, the structural stress of the weld is calculated with the S-N curve method, and the fatigue life of dangerous weld position is analyzed. The results showed that the maximum von Mises stress occurred on the weld toes of fillet weld between sealing plate and gusset plate end. The fatigue life of dangerous parts of sealing plate weld can not meet the safe service requirement of 30 a of quayside container crane.