The 74 m-long and 1.5 m-diameter steel tube piles are driven into Yangpu harbor of Hainan province.According to the whole-process PDA test,pile pressing test,pile pulling test and axial force test,we discuss the distributing law of shaft friction on compressive and tensile load of large diameter and super-long steel tube piles in deep clay area and draw the conclusions as follows.Firstly,along with the increase of penetration,the shaft friction of the same soil increase,but after reaching certain depth of the penetration,its amplification reduces and becomes steady.Secondly,the shaft friction of large diameter and super-long steel tube piles under compressive load is 56.9%～75.0% of its under tensile load.Thirdly,only when the displacement of pile top reaches 1.1%～1.3% of its diameter,tip resistance of large diameter and super-long steel tube piles can be fully functional,and it is about 19% of carrying capacity.Furthermore,the distributing law of shaft friction on compressive and tensile load in deep clay area is discussed can give instruction to the bearing capacity of large diameter and super-long steel tube piles for theoretical research and engineering practice.