Li-rich Mn-based Li1.2Ni0.2Mn0.6O2 cathode materials were synthesized by freeze-drying assisted sol-gel method, and its structure, morphology, and electrochemical performance were compared with the same materials synthesized by traditional sol-gel method. XRD results show that the Li1.2Ni0.2Mn0.6O2 powders synthesized by freeze-drying assisted sol-gel method exhibit lower cation mixing, and the crystalline structure is improved by the presence of freeze-drying process. SEM images indicate that the extent of particle agglomeration of the materials synthesized by freeze-drying assisted sol-gel method is lower compared to the sol-gel sample. Electrochemical test results indicate that the materials synthesized by freeze-drying assisted sol-gel method exhibited better rate capability and cyclability. Besides, EIS results suggest that the charge transfer resistance of Li1.2Ni0.2Mn0.6O2 synthesized by freeze-drying assisted sol-gel method is much lower than that of the Li1.2Ni0.2Mn0.6O2 prepared by sol-gel method, which enhances the reaction kinetics.