The unique features of deep eutectic solvents (DESs) have sparked interest in their use for various applications due to their capacity to introduce new functional groups and other surface alterations. In this study, DESs were employed for the surface modification of MWCNTs. Twelve distinct varieties of Choline chloride-based DESs were prepared and characterized. Prior to the MWCNTs functionalization process, further tests, including viscosity, density, and TGA analysis, were carried out to evaluate the stability of the prepared solvents. The surface functionalization of MWCNTs was then carried out using the most stable solvent. The DESs-functionalized samples were tested for dispersibility and solubility, and FTIR was used to confirm the functional groups present. In comparison to the pristine MWCNTs, the result showed that samples D1, D2, and D4 had several functional groups on their surfaces. Also, in comparison to other DESs-functionalized samples, D1, D2, and D4 had more oxygen-containing groups, as further corroborated by CHNS analysis. As a result, DESs comprising glycerol and ethylene glycol provide an environmentally benign route to alter the surface of MWCNTs, making them suitable functional materials for a range of uses such as Adsorbents, Catalysts, Li batteries, EMI shielding materials, and Supercapacitor electrolytes. © 2024 Elsevier B.V.