The present work investigates the excitonic effects on the bilayer graphene with layers of differentthickness under the influence of external electric field through a simple numerical approach. The bandstructure and energy gap have been calculated using a tight-binding model including parameters likethe second-nearest-neighbor-hopping energies t(in-plane) and (intra-layer) and the on-site energy, in details. The binding energy of exciton for bilayer graphene has been calculated by Wannier modeland Hartree-Fock approximation through the Bethe-Salpeter equation. Finally the optical conductivityspectrum of bilayer graphene has been calculated by using the effective mass approximation in two bandmodel. © 2013 Elsevier GmbH. All rights reserved.