Abstract: In this paper the spline subdomain method is applied to the analy sis of folded plate structures. The cubic B-splines and the series which satisfy the boundary conditions are used for the approximate displacement functions of foldad plate structures. Applying the principle of minimum total potential energy, the spline subdomain method of folded plate structures is derived. in comparison with the ordinary finite method or finite strip methol, the main features of the presented method are of higher aceuracy. less unknown coefficients, easily programmig, etc. A numerical solution is given. The results show that the presented method is quite effective.