Present work describes the inverse problem for identification of material and support type properties of flexible dolphin structure. Most liquid bulk terminals are equipped with a jetty as berthing facility. The ship mostly berths to dedicated breasting dolphin structures, which can be single-pile flexible/rigid dolphins or multi-pile flexible/rigid dolphins. This work considers dolphin motion as mass-spring damped system where cantilever approximation mimics dolphin pile. Few measurements have been made for the dolphin structure, which is approximately 30 m long, 15 m immersed in the bottom and placed about 2-3 m above the sea level. The elastic material properties and pile support were identified via inverse method combined with displacement measurements of dolphin head.