Abstract: The new process of extracting lithium from lepidolite by alkali dissolution was studied.Based on the research for the influences of alkali concentration，solid-liquid ratio，reaction temperature，and reaction time etc.on the conversion rate of lithium in the lepidolite，the optimum conditions for processing lepidolite by alkali dissolution were established，i.e.the mass fraction of alkali was 50%，the solid-liquid ratio（lepidolite powder to alkali solution） was 1∶3.5，the reaction temperature was 190 ℃，and the reaction time was 4 h.The conversion rate of lepidolite was 98.2% under above conditions.The main advantages of this method include：1）The lithium in lepidolite 100% into the solution；2）Extracting lithium/cesium/rubidium from lepidolite can be completed in one operation；3）Do not generate hydrofluoric acid corrosion for equipment due to the environment of alkaline liquid ；4）As the by-product is the wide-applied aluminum-silica sol，through the by-product sales can greatly reduced the cost of extracting lithium.

Key words: lepidolite, alkali dissolution, lithium extraction