In this study, purification and molecular weight of the digestive lipase was described for the first time in Galleria mellonella. It was extracted from the midgut of the last larval instar and partially purified by ammonium sulphate and sephadex G-100. The results indicated that the purified enzyme has specific activity of 2.68 U mg^–1, recovery of 18.3% and purification fold of 49.15 and has a 104.23kDa molecular weight. The purified enzyme was further characterized for its activity at different temperatures and pH values. The highest activity was at 37˚C and pH 7. Also, the enzyme activity was tested against some inhibitors (EDTA, PMSF and EGTA) and activators (CaCl₂, NaCl and KCl). It was observed that lipase was inhibited and activated with all used chelating agents and activators, respectively. The kinetic parameters of this enzyme were determined as they give us important information about the enzyme behavior and efficiency. The results revealed that the enzyme needs a high concentration of P-NPB (used as substrate) to achieve its maximal velocity. The enzyme showed K_m of 381.46 mM using P-NPB as a substrate. These results will help in developing new pest control strategies targeting pest physiology.