Green chemistry plays a very important role in the sustainable development, seeking to reduce and prevent pollution at its source, minimizing the hazard and maximizing the efficiency of the chemical processes. Ionic liquids (ILs) are a new generationof chemicals that have a great potential for contributing to the greenness of chemical processes and developing new applications,both being of interest for the pharmaceutical industry. This workdeals with the development of ILs as greener alternatives for some of the processes within the frame of green chemistry. It focuses on the environmental impact of the ILs, their ecotoxicity and potentialbiodegradability, compiling results of different ecotoxicological studies. ILs have the reputation of being “green” chemicals, but not all of them can pass favourably the tests evaluating their environmental effects.