Influence mechanisms of loading sequence on pile-soil interaction of negative skin friction (NSF) are simply analysed. Finite element method is used to calculate the differences. Analysis results show that changes of loading sequence would induce the changes of friction distribution in pile

neutral point position and the downdrag caused by NSF. Differences of friction distribution is mainly amount of negative skin friction in upper part of pile

negative skin friction is smaller when negative skin friction appears first; and it does not change with load of pile. Position of neutral point is lower

when negative skin friction appears first; the differences increase as vertical load of pile increase. When negative skin friction appears first

downdrag is smaller than that of pile load applied firstly; the difference increases as load of pile increase. The results will be useful to the research and application for checking negative skin friction.