Abstract: The provisions about the stability capacity of members with single angle section are simple or have not been provided in Chinese Code for Design of Steel Structures (GB50017—2003). In order to solve this problem, in this paper, the principles of angles subject to compression and bending were introduced according to foreign codes such as ANSI/AISC360—2010, BS5950—1:2010, Eurocode 3, etc. It is somewhat questionable when single angle with b/t≤20 does not require the computation of flexural-torsional buckling in AISC code and may be conservative to single angle flexural member when using BS5950. The authors proposed three main questions which were answered in the future codification: 1) research of flexural capacity of single angle should be carried out; 2) a unified concept, unstiffened element should be applied to these sections such as angle leg, I or C-shapes, and the web-flange interaction should be considered; 3) the member capacity considering local buckling should be adopted instead of overall stability and local stability.