The ship to ship LNG berth has high requirements for mooring stability.At present,there is no quantitative analysis method for mooring stability analysis of ship to ship moored berth when affected by ship wave.Combining with the engineering case,we apply Flory-Remery method of calculating single ship wave load produced by passing ship,modify the Flory-Remery method according to the characteristic of ship to ship berth,and analyze dynamic effect on moored ships’mooring stability when affected by passing ship quantitative.The results show that under the condition of typical moor,spring line’s load and ships’ surge of ship to ship moored berth are most affected by ship wave.The mooring stability cannot satisfy the requirement when the distance between moored ships and passing ship is 50 m,and it can satisfy the requirement when the distance is 100 m.When the distance between moored ships and passing ship is 150 m,the mooring stability of ship to ship berth is largely unaffected by ship wave.