The PARs are G-protein-coupled receptors. Studies have found that the 4 subtypes (PAR-1, PAR-2, PAR-3 and PAR-4) of PARs are closely related to the occurrence and development of digestive tract tumors. The pathophysiological role of PARs in the digestive tract and gastrointestinal tumors was reviewed and summed up in this paper, with emphasis on the expressions and mechanisms of PAR-2 and PAR-4 in digestive tract tumors, as well as the role of PARs in the development of digestive tract tumors.