This paper discussed fatigue characteristics of steel pipe structure with gusset plate connection in which branch tube axis is eccentric for the main tube axis. The authors conducted the static experiment in order to ask for the buckling strength of a main tube as past research using the test specimen that consists of a main tube and a branch tube. On the basis of the past researches, this experiment performs low-cycle repeat loading to a branch tube while carrying out loading of the fixed load to a main tube. Based on this study result, the stress behavior and fatigue characteristics of the main tube of steel pipe structure that have the eccentric joint were clarified.
