The most important use of lepidolite has been as a minor ore of lithium metal. This use was more important in the first half of the 1900s than it is today. Today most lithium is produced from brine and evaporite deposits in South America, where lithium can be extracted more economically.

Small amounts of rubidium sometimes substitute for lithium in the lepidolite crystal lattice. When present, the rubidium can be recovered as a byproduct during the extraction of lithium. Lepidolite and pollucite, another lithium mineral that can contain significant amounts of cesium, often occur together. These minerals can be mined for lithium with cesium as a byproduct.

Lepidolite is sometimes used as a source of flake mica. It is also used to make glass and as an ingredient in some enamels. Lepidolite can be used as an ornamental stone and is an important constituent in some gem materials.