This paper presents an investigation on the conduction behaviors of the anisotropic conductive film (ACF) interconnections bonded at various bonding forces. The connection resistance of the ACF joints decreased with increasing bonding force up to 70 N, but subsequently converged to a value of 10 mΩ at bonding forces above 70N. This convergence of the connection resistance in the ACF joints was due to two opposing factors: decreased resistance due to increased contact area and increased resistance due to decreased currentflow path that may have been affected by the delamination of the metal film from the polymeric cores at high bonding forces. During thermal shock testing of the adhesive joints, two different conduction behaviors were observed: increasing connection resistance and the termination of Ohmic behavior. The former was due to decreased contact areas caused by warpage of the package, whereas the latter was caused by delamination at the interface.