Idiopathic pulmonary fibrosis is one of a group of chronic interstitial lung diseases of unknown causes, and is characterized by alveolar epithelial cell injury, abnormal proliferation of fibroblasts and excessive deposition of extracellular matrix. There are limited therapeutic options, poor prognosis, low long-term survival rate and is associated with increasing incidence since the pathogenic mechanisms are elusive. This demands a better understanding of the molecular mechanisms underlying the pathogenesis. It is most essential to know the onset and progression of this disease, especially in relevance to human health. In this paper, we reviewed the advances in research of idiopathic pulmonary fibrosis.