The observation of short halogen-carbonyl oxygen interactions in protein-ligand complexes has spurred us to use computational tools to better understand the strength of halogen bonding interactions. In this study we have produced potential energy curves for the halogen bonding interactions of several halobenzene-formaldehyde complexes. It was found that, for most halogen substituents, a halobenzene and formaldehyde form stable halogen bonded complexes with interaction energies that increase as the size of the halogen substituent increases.