This study aims at investigating a better condition of calcination at different temperature to produce LiMn2O4 microstructure. In this study, cubic LiMn2O4 was synthesized using a low temperature solid-state reaction. We report, here, MnO2 nanorods synthesis by reflux and their chemical conversion to LiMn2O4. The compound was characterized by XRD and TEM. Further, the analysis of LiMn2O4 microstructure was carried out by Direct Method using winPLOTR package program and Diamond using XRD data. At low calcination temperature, Mn2O3 is present as an impurity, but it disappears along with the increase in calcination temperature. It is also found that solid state reaction at is 750oC give nanoLiMn2O4. The lattice parameters and cell volumes of LiMn2O4 increases with the increase in heating temperature.