Electrical energy storage is absolute for complete usage of all renewable energy sources. Herein, we have studied the electrochemical performance of Chevrel phase Mo6S8 as cathode material towards rechargeable Mg battery. Solution chemistry route is adopted for the synthesis of Mo6S8. The morphology, phase purity is analyzed by Scanning Electron Microscopy, Transmission Electron Microscopy, and X-Ray Diffraction techniques. The cyclic Voltammetry and Galvanostatic charge-discharge studies confirmed the reversibility of Mg-ion insertion. Herein, Mo6S8 cubes show excellent capacity retention of 70 mAh g(-1) for 200 cycles at C/5 rate. The role of CNT in improving rate performance was also demonstrated. The reasonable reversible capacity, rate performance, and cycling stability reveal the feasibility of Mo6S8 material for future rechargeable Mg battery. In order to study the kinetics of Chevrel phase compound upon cycling, EIS study was carried out. The redox process upon insertion/extraction is investigated by X-ray Photoelectron spectroscopy which shows no change in oxidation state of a transition metal.