Lignin represents one of the promising renewable sources of benzene derivatives for industrial exploration. It is the second most abundant biopolymer on Earth and makes up about 30% of non-fossilized organic carbon. In this connection currently a lot of attention is paid to elaboration of environmentally benign and economically reasonable procedures for lignin depolimerization/modification.1 One of the promising way to figure out this problem is to utilize the ozonolitic cleavage in non-classical solvents. We present in the current communication results on the use of Deep Eutectic Solvents (DESs) as green media for biomass procesing, 2 which can be used in ozonolitic transformations to diminish the negative impact of traditional volatile and toxic organic solvents. For this purpose, some DESs such as Malic acid – Proline (1:3), Choline chloride – Glycerol (1:2), Choline chloride – Urea (1:2), Choline chloride - Propylene glycol (1:3), Choline chloride - Ethylene glycol (1:3) have been obtained and their properties investigated. Acceptance criteria included a wide liquid range (below 15 oC), chemical stability (determined by NMR after O3 treatment) and dissolution power (5 to 10 w/w % of lignin). Investigated lignins included commercial Kraft lignin, as well as lignins isolated from local raw materials: residual grape seeds after grape seed oil production, walnut shells and internal membranes. These materials are valuable wastes of agricultural processing which could be conveniently explored. Extraction of lignin was performed with dioxane in a Soxhlet continuous extractor after a preliminary removal of lower molecular weight polyphenolic compounds with an ethanol-benzene mixture. As a result, two choline based DESs showed acceptable properties, and ozonolysis experiments were performed. The obtained degradation products were separated into low and high molecular weight fractions by extraction with a suitable organic solvent, sedimentation with water and further investigated either by GC-MS or NMR. In particular HSQC and DOSY experiments proved to be efficient analytical tools to show cleavage of specific bonds from the complex lignin structure.