The initial Coulombic efficiency (ICE) of electrode materials is closely related to the energy density of lithium-ion batteries (LIBs). However, some promising electrode materials for next generation LIBs suffer from low ICE, which inevitably hinders their practical application. Among the discovered modified strategies for LIBs, electrolyte optimization has attracted extensive attention due to its facile operation process. Herein, the role of ICE in LIBs is first analyzed. Subsequently, the recent progress on effective electrolyte optimization strategies for boosting ICE in LIB is summarized (including the optimization of lithium salt, salt concentration, solvent, and electrolyte additive). Finally, future research directions of electrolyte optimization for boosting ICE are proposed. This review provides valuable guidance for developing advanced electrolyte for LIBs.