Abstract: Initial imperfections in actual plate structures have impact on the structural stability and safety.Considering actual steel structures as a research background,with emphasis on the effect of initial imperfections,the nonlinear stability of stiffened plates was analyzed under the condition of different initial imperfection sizes,stiffener types,loading ways and boundaries.As for a simply supported plate,the thinner the plate,the more remarkable the influence of initial imperfections is.Considering the same initial imperfections,the nonlinear buckling value of flat steel is the largest.The influence of initial imperfections on the nonlinear stability of plates is large under uniaxial loading.Initial imperfections impact on a simply supported plate or a consolidated plate stable.