The influences of lattice vacancies and lattice impurities on the electronic structures and floatability of spodumene were studied by the density functional theory (DFT) through analysis of partial density of states (DOS), Mulliken population, differential charge density, and frontier molecular orbitals. The calculation indicated that the effect of lattice Al, Si, and Li vacancies on the DOS, Mulliken population as well as the interaction between spodumene and oleate was insignificant. Cr, Fe, and Mn impurities caused the shift of Fermi level towards lower energy and the occurrence of peaks of impurity near Fermi level. K and Na impurities contributed little to the lowest unoccupied molecular orbital (LUMO) of spodumene, while Cr, Fe, and Mn impurities had great contribution, suggesting that Cr, Fe, and Mn impurities significantly affected the interaction between spodumene and oleate. The frontier molecular orbitals analysis indicated Cr, Fe, and Mn impurities are in favor of oleate adsorption.