'''Chemical evolution''' may refer to: * Abiogenesis, the transition from nonliving elements to living systems * Astrochemistry, the study of the abundance and reactions of molecules in the universe, and their interaction with radiation * Cosmochemistry, the study of the chemical compositions in the universe and the processes that led to them * Evolution of metal ions in biological systems, incorporation of metallic ions into living organisms and how it has changed over time * Gas evolution reaction, the process of a gas bubbling out from a solution * Molecular evolution, evolution at the scale of molecules * Oxygen evolution, the process of generating molecular oxygen through chemical reaction * Stellar nucleosynthesis, the creation of chemical elements by stellar thermonuclear fusion or supernovae {{disambiguation}}