By using a needle-like raw material γ-MnOOH as a Mn-source, single crystals of lithium manganese oxides were synthesized in a variety of lithium-containing fluxes including LiNO 3 , Li 2 CO 3 , LiOH, LiCl and Li 2 SO 4 . Needle-like Li 1.33 Mn 1.67 O 4 and Li 2 MnO 3 crystals and plate-like polyhedral Li 2 MnO 3 crystals were obtained in an LiNO 3 flux heated within different temperature ranges (300–400, 500–750 and 900–1000 °C, respectively). Not only polyhedral and film Li 2 MnO 3 but also octahedral LiMn 2 O 4 single crystals were obtained in an LiCl flux by use of different shaped containers to control the exposure to the atmosphere. Orthorhombic LiMnO 2 crystals with tube- and rod-like shapes could be obtained at the bottom of the LiCl melt at 1000 °C. The lithiation reaction (at low temperature) and dissolution–precipitation controlled growth (at high temperature) of Li 2 MnO 3 were also observed in Li 2 CO 3 and LiOH fluxes. According to the reaction mechanism, the Li-containing fluxes investigated can be classified into four types: (1) LiNO 3 , oxidizing flux; (2) LiCl, non-oxide flux; (3) LiOH and Li 2 CO 3 , oxidic, but non-oxidizing fluxes; and (4) Li 2 SO 4 , no reaction.