Barium titanate (BaTiO3) is a common ferroelectric material with perovskite structure widely used for the production of a variety of electro-optical devices. When doping with rare earth elements, very interesting characteristics can be attributed to BaTiO3. Among the methods used to synthesize BaTiO3, wet chemical approaches are the most suitable for preparing homogenous and pure nanostructured materials. In this sense, the present article aims to summarize the state-of-the-art of the most relevant wet chemical routes for the synthesis of nanocrystalline BaTiO3 doped with rare earth (RE) ions (BaTiO3: RE), which include the following: sol-gel, sol-emulsion-gel, Pechini, solvothermal/hydrothermal, and co-precipitation methods. The influence of each method on morphology and particle size, as well as on the dielectric and/or luminescent properties of the powders is discussed.