The complexation process between benzo[a]pyrene (BaP) and γ-cyclodextrin (γ-CD) was computationally studied using DFT methodology. Several initial configurations of the interaction of BaP with γ-CD were explored to determine the most stable inclusion complex. According to the calculated complexation energies, the BaP/γ-CD complex is found to be the most favorable energetically when the BaP guest is totally entrapped into γ-CD cavity. The inclusion process involving the encapsulation of two guests BaP in the cavity of γ-CD is also thermodynamically favored. Van der Waals interactions play a determinant role in stabilizing BaP/γ-CD and 2BaP/γ-CD complexes.