Oleg V. Prezhdo (born 1970) is a Ukrainian–American physical chemist whose research focuses on non-adiabatic molecular dynamics and time-dependent density functional theory (TDDFT). His research interests range from fundamental aspects of semi-classical and quantum-classical physics to excitation dynamics in condensed matter and biological systems. His research group focuses on the development of new theoretical models and computational tools aimed at understanding chemical reactivity and energy transfer at a molecular level in complex condensed phase environment.