Abstract: Protein tyrosine phosphatases (PTPs) are a large and structurally diverse family, and contain a highly conserved catalysis domain. In plants, they interact with the mitogen-activated protein kinase (MAPK), which has an important role in development, cell proliferation, hormone regulation and stress signaling. PTP is a negative regulating factor in the MAPK pathway.In this paper, we review the recent advances in study of PTP and the role of MAPK in plants, including the structure of PTP and its functions in the MAPK pathway, especially in Arabidopsis thaliana.