Currently, lepidolite is considered an important natural alternative for obtaining lithium, given the difficulty in processing other species containing this metal. However, its mechanical preparation and beneficiation present considerable challenges and play a critical role in its efficient separation by flotation. This study explores the effect of particle size and dodecylamine concentration during flotation in a laboratory Denver cell. The results indicate that particle size significantly affects the finding in which the optimum was −90 + 75 μm, with a separation efficiency of 94%, and with only 2.067 × 10⁻⁵ M of dodecylamine (DDA) (5 g/t) at pH 11.0. The hydrophobicity of lepidolite was generated by the effect of the chemisorption of the cationic collector and the FTIR results indicate detection of the characteristic bands of the adsorption of DDA to the surface of lepidolite.