Lipoxygenases (LOXs) are dioxygenases that catalyze the formation of corresponding hydroperoxides from polyunsaturated fatty acids such as linoleic acid and arachidonic acid. Thre are six LOX isoforms have been found in the humans and mice. 5-Lipoxygenase (5-LOX) is a distinct isoform playing an important role in asthma and inflammation. 5-LOX causes the constriction of bronchioles in response to cysteinyl leukotrienes such as LTC4, thus leading to asthma. 5-LOX also induces neutrophilic inflammation by its recruitment in response to LTB4. 12-Lipoxygenase (12-LOX) is an isoform expressed in epithelial cells and myeloid cells including platelets. 12-LOX can be found in the epithelial cells of the skin. 12-LOX is a potential target for novel anti-platelet therapeutics.15-Lipoxygenase (15-LOX) is expressed in epithelial cells and leukocytes, has different substrate specificity in the humans and mice.15-LOX-1 is a target of nonsteroidal anti-inflammatory drug-induced apoptosis in colorectal cancer cells.