The seismic retrofit of existing port structures is dependent on type of structures, usages, required performance, and so forth. Also, the damage situation should be considered for recovering structures after strong quakes. Therefore, there are lots of methods developed with various mechanism and performance.
　In this paper, typical damage patterns, studies on damage mechanism, types and concepts of recovering methods and some case studies of retrofit on existing facilities and recovering on damaged structures are described．These data could be helpful to reduce seismic damage of existing structures from huge earthquakes in close future or to make quick and more reasonable decision for recovering.
　In the section of seismic damage, typical seismic damages of most familiar structures are described in order to understand what could happen on structures during or after earthquakes. The studies of damage mechanism are composed of detailed numerical analyses combined with verification tests with small scale quay wall model. The section of retrofit and recovering methods includes introduction of applicable methods for each type of structures, mechanism and case studies of these methods. Finally, several examples of recovering and retrofit projects are mentioned.