To ensure the mooring safety of floating bollards in service，based on a representative ship lock of the Beijing-Hangzhou Grand Canal，according to the actual structural characteristics of floating bollards and the basic principles of mathematical mechanics，this paper deduces and constructs an expression that can reflect the quantitative relationship between the strain signal of floating bollards and the mooring force of ships.On this basis，a set of monitoring methods for the safety of mooring lines of floating bollards of ship locks are proposed.To verify the reliability of the safety monitoring method，field test is carried out on the representative floating bollards in the ship lock.By comparing the ship mooring force obtained by the safety monitoring method in this paper with the mooring force measured by the traditional load measurement method，it is found that the relative error between the two is less than 15%，which indicates that the safety monitoring method of the ship lock floating bollard mooring line proposed in this paper has high measurement accuracy.