Discoidin domain receptor 1 (DDR1) is a collagen-activated receptor tyrosine kinase. Upon collagen binding, DDR1 undergoes tyrosine autophosphorylation, which consequently triggers downstream genetic and cellular pathways and plays critical roles in the regulation of cellular morphogenesis, differentiation, proliferation, adhesion, migration, and invasion. Its expression is mainly limited to epithelial cells located in several organs including skin, kidney, liver and lung. Increasing evidence suggests the potential roles of DDR1 in various human diseases including cancer, fibrosis, atherosclerosis, and other inflammatory disorders. Modulating the activity of DDR1 may be considered as a new therapeutic strategy for human cancer and inflammation-related diseases.