Aim. Analysis of the hydration changes at formation of DNA complexes with biologically active aromatic compounds (BAC): antibiotics actinomycin D, daunomycin, nogalamycin, novantrone and mutagens ethidium bromide and proflavine. Methods. Molecular dynamics simulations. Results. The hydration indexes for double-helical DNA and ligands in a free and complexed states were calculated. A critical analysis of modern ideas about changing water environment at binding of aromatic ligands to DNA was performed. Conclusions. It is shown that upon binding of aromatic BAC with DNA a significant (from 2.6 for novantrone to 13.1 for actinomycin D) liberation of water molecules out of hydration shells with the disruption of hydrogen bonds takes place.