Since the application of solvents in producing industrial important chemichals is unavoidable, in the last decade new and environmentally friendly solvents are intensively explored. Deep eutectic solvents belong to the new generation of non-volatile and stabile solvents, and are intensively studied as a replacement for organic solvents in chemical and biotechnological industry. In order to gather knowledge about lipase behaviour in these new solvents, within this work the stability of lipase in cholinium-based deep eutectic solvents was studied.