The limit value for the widthtothickness ratio of the hotrolled equilateral angle steel member from ‘Guide for design of transmission tower’ by American Society of Civil Engineers and ‘Technical Regulation of design for tower and pole structure of overhead transmission line’（DL/T51542002） in China is discussed. And the different method of dealing with local buckling instability of single angle columns is compared. With six group axial compressed test of different slenderness ratio, it is found that the current structural design standards DL/T51542002 used in the calculation of highstrength steel stability is conservative. According to finite element method(FEM), the strength subtraction coefficient under axial compression in DL/T51542002 is amended.