Periostin (POSTN) is a cell adhesion protein. Under physiological conditions, it plays an important role in the formation of bone and teeth, can promote development of the heart valves and participate in the pathophysiological processes of various heart diseases. In recent years, POSTN has been found to be highly expressed in a variety of malignancies and is often associated with recurrence and metastasis as well as poor prognosis. As an extracellular matrix protein, its role and mechanism in the development of tumors has attracted increasingly attention in many researches. Here, the authors address the research progress of POSTN in tumors.