The main objective of this work is to evaluate the buckling capacity of a mixed adhesively lab joint panel when subjected to in-plane shear loading. In the plate joints, two types of adhesive were used in the overlap region and the stiff adhesive was located in the middle. This technique proposes to modify the mechanical properties of adhesive along the overlap. The adherents used in the investigation are made up from homogeneous isotropic material and laminated composite. Three-dimensional finite element models were developed for mixed adhesively bonded isotropic and orthotropic panel pairs. Linear finite element models have been developed to understand how variable modulus bond line affected the buckling loads. Finite element analyses were performed to predict buckling loads for different adhesive Young's modulus ratios and different adherent material types in the first five modes.