Among bee venom proteins, phospholipase A2 (PLA2) is critical one of bee venom components to defend against predators intruders. In this study, PLA2 gene from cDNA libarary using the venom glands of Bombus ignitus worker bees(BiVn-PLA2) was cloned and characterized. BiVn-PLA2 spans 2211 bp and consists of three introns and four exons encoding 180 amino acid residues. BiVn-PLA2 shares high levels of identity with a bumblebee, B. terristris (89% protein sequence identity), B. pennsylvanicus (88%), and a honey bee, Apis mellifera (53%). Northern blot analysis revealed that BiVn-PLA2 is expressed in venom gland, indicating that BiVn-PLA2 is one of the venom components of B. ignitus. To determine BiVn-PLA2 of venom components from venom sac, N-terminal amino acid sequencing of a putative BiVn-PLA2 (the purified 18 kDa) was performed by Edman degradation. The N-terminal amino acid sequencing of the 18 kDa protein was coincident with the N-terminal amino acid residues of the mature BiVn-PLA2 and the 18 kDa protein catalysed the hydrolysis of DBPC subs trate[1-O-(6-Dabcyl-aminohexanoyl)-2-O-(12-(5-B ODIPY-entanoyl) aminododecanoyl)-sn-glyceryl phosphatidylcholine] that is a sensitive fluorogenic probe for PLA2 activation. Western blot analysis revealed that BiVn-PLA2 is expressed in the venom gland, stored in the venom sac, and then emitted throughout sting apparatus. Finally, to test BiVn-PLA2 toxicity, BiVn-PLA2 was adjusted to a insect cell (Sf9) at different concentrations (1-30 μg/2×105 cells). The apoptotic cell death assay results showed that the cell survival decreased with increasing concentrations (1-30 μg/2×105 cells).