Abstract: The soften effect of the cyclic wave loading and construction disturbance during shield passing through the breakwater on the beneath soft clay ground is examined and the static mechanical behaviour (shear strength, stiffness, etc.) of the marine soft soil after coupling of shield construction disturbance and wave loading are investigated in this paper. A serious of hollow cylinder apparatus (HCA) undrained shear elementary tests of the soft clay after coupling between shield construction disturbance and wave loading are conducted, in which the stress loss induced by the ground loss during the shield construction is modeled through gradually reducing the confining pressure and the long-time wave loading is simulated by the 3,000 cyclic loading. The experimental results show that (1) both the shear strength and stiffness of the soft clay increases with the increasing confining pressure. However, they both decrease with the increasing wave cycles and ground loss rate (δ) under the same confining pressure. (2) Under the same wave cycle shear times, the initial tangent modulus of the soft clay decreases linearly with the increasing soil loss (δ) under the same wave cycle. However, both the cohesive force and internal friction angle decrease nonlinearly with the increase of δ. Above all, both the shear strength and stiffness of the soft clay are reduced in different amplitudes after the coupling actions of wave loading and shield construction. It is suggested that full attention should be paid to the soften effect on static mechanical behaviour of soft clay after the coupled disturbance effect of shield construction and wave loads in practical engineering.