Pulse granuloma is a distinct oral entity characterized as a foreign body reaction occurring either centrally or peripherally. It is usually seen in the periapical or in the sulcus area. Occasionally the lesions occur in the wall of the cyst, commonest being the inflammatory odontogenic cyst. Histologically, they present as eosinophilic hyaline mass with giant cell inclusions and inflammatory cells. They may show different histological characteristics, possibly related to the length of time in the tissue. Adequate recognition is important to avoid misdiagnosis. Many authors suggest that pulse granuloma results due to implantation of food particles of plant or vegetable origin into the tissue following tooth extraction. This paper aims to report a case of pulse granuloma associated with keratocystic odontogenic tumor with its histochemical and polarizing microscopic features and discuss on etiopathogenesis of pulse granuloma.