In the present paper, new nondimensionalized parameters, namely, nondimensionalized axial and bending stiffnesses have been introduced to study analytically the buckling behavior of two-layer beams with separated delaminations. Numerical analysis has been carried out by using ANSYS software to validate the developed analytical model. Delaminations are modeled with gap elements in ANSYS. A detailed parametric study has been carried out and it is found that the buckling behavior strongly depends on these new nondimensionalized parameters. Another nondimensionalized parameter, effective-slenderness ratio is also introduced and it is found to be a controlling parameter of delamination buckling mode configurations.