Three analytical approaches are used to evaluate the effect of curvature on the elastic local buckling behavior of horizontally curved I-girder flanges. First, the inside and outside halves of the flange are treated separately and an energy method is applied to obtain buckling solutions for a flat plate subjected to linear varying edge stresses simulating the effects of combined bending and torsion on the girder. Support conditions for the flange-web juncture are idealized as simply supported and fixed. Second, a governing differential equation for the full flange plate with linearly varying edge load is derived in Cartesian coordinates and the equation is solved by Galerkin's series approximation. Numerical results are presented for various warping-to-bending stress ratios. Third the problem is solved using the finite element method and the results are compared with the energy method and the Galerkin's series method. The effect of curvature on the elastic buckling behavior of the flange plates is observed and the applicability to curved girders is demonstrated.