In allusion to the question of oblique berthing in small vessels,this paper receives the calculation method of ship collision energy in this situation based on British Standard:Maritime Structures-Part 4:Code of practice for design of fendering and mooring systems(BS 6349-4:1994).Taking one inland river wharf in Guangzhou for example,this paper discusses the strength and deformation of the steel cluster pile structure under the action of ship impact force in difference angles.The results show that when the small vessel berths obliquely,its tangential impact force can not be ignored.For the steel cluster pile of this engineering project,the ship’s impact force,the maximum strength and the maximal displacement of pile presents the trend of increasing at first and then reducing accompanied by the ship impact angle,and the most unfavorable impact angle of the ship is almost from 20°~22°.To ensure the application safety of the structure,we suggest to consider adequately the importance of oblique berthing of small ships in similar projects.