"Green" chemistry is part of chemistry that is intensifying in the last two decades, which among other things puts the use of substances that are not dangerous to humans and the environment as a priority. As a potential substitute for organic solvents, which volatility and toxicity negatively affect human health and the environment, ionic liquids and eutectic solvents are increasingly used. Because of its properties, ionic liquids can be adapted to the specificities of different processes, and their application has been found in a large number of industrial processes for purifying gases or soils all the way up to biodiesel production. They are simply synthesized and can adapt to process requirements, but their ecological acceptability has become questionable. In some cases, in the synthesis of ionic liquids, substances of adverse environmental effects are used, which by their release can cause negative effects on ecosystems or, for example, toxic salts that are harmful to human health can be used. Eutectic solvents, unlike ionic liquids, can be prepared from natural substances and therefore have no negative effect on the environment that is their primary advantage over ionic liquids. The application of eutectic solvents is already well-spread and they are used in electrochemical processes, synthesis of materials and biodiesel purification. At this point there is a whole series of evolving processes in which eutectic solvents are used and therefore it is expected that eutectic solvents, as well as ionic liquids, will find a wide industrial application.