Today allergens are known as molecules that induce an IgE-mediated reaction (allergy) in human beings. Protein is one of the most important molecules that could be the allergen. Allergens sources are varied from plants, animals, and fungi to microbial and even viral sources. Melittin, phospholipase A2, hyaluronidase and venom allergen-5 are most important venom allergens in hymenoptera family. The various components are identified as the venom allergens in scorpions and snakes venoms. VAH (Vespid allergen antigen homolog) and ASP (Aspergillus allergen) are two venom allergens group detected in nematode parasites. Recognition of venom allergens and their immune responses is the first step to avoid the animal-related allergic diseases and prevent anaphylactic shock.