Molecular parameters (interatomic distances and angles, total atomic charge, dipole moments) of DHEA (Dehydroepiandrosterone), serotonin and of their putative complex including its heat of formation, have been computed in an ab initio comparative study involving HF and DFT calculations. The 6-31G* basis set and the B3LYP functional were employed. The aim of this study is to emphasize by DFT calculation the possible existence of a complex between DHEA and serotonin that may have the properties of a new drug. A Natural Bond Orbital analysis description offers supplementary details for the structure of the molecular units and their interaction.