This chapter presents the modeling and the finite element analysis of the linear elastic buckling of different cold formed steel sections using the so-called (cFEM) software, the. sSections analyzed with different shapes were analyzed such thats C-section, LSB section, column, orand beam with various lengths starting from short to intermediate and. also lLong thin-walled cold formed steel hwas beenalso analyzed, as were the width of the lips, the flange and web, and different perforation pattern,s.