Prostaglandins (PGs), small lipid molecules derived from arachidonic acid by COX enzymes, are critical mediators of allergic inflammation. Our understanding of the role of PGs in allergic lung inflammation has been hampered by the very short biologic half-life of these mediators, which has made mechanistic studies difficult in human subjects. However, advances in molecular biology and pharmacology have given investigators the opportunity to examine the role of specific prostanoids in the development of allergic inflammation in animal models. Studies investigating specific PG receptors are also elucidating the mechanisms by which PGs regulate the pulmonary allergic phenotype. This review summarizes the current literature on the role of PGs and PG receptors in allergic lung inflammation.