Cancer　is　a　serious　disease　that　endangers　human　health.　Solid　tumors　are　surrounded　by　extracellular　matrix,　infiltrated　immune　cells,　and　the　secretum　of　surrounding　mesenchymal　cells.　The　tumor　microenvironment　plays　a　key　role　in　tumorigenesis,　tumor　growth,　and　resistance　to　antineoplastic　therapy.　Plasminogen　activator　inhibitor-1　(PAI-1)　is　an　important　regulatory　factor　in　tumor　microenvironment.　PAI-1　not　only　functions　as　a　key　constitution　with　tissue-type　plasminogen　activators　(tPA)　in　regulating　fibrinolytic　activity,　but　also　participates　in　invasion,　infiltration　and　migration　of　tumor.　In　this　paper,　the　structure　and　function　of　PAI-1　and　its　significance　in　tumor　microenvironment　in　recent　years　are　reviewed.　It　is　considered　that　PAI-1　may　be　an　important　target　for　anti-cancer　therapy.　At　the　same　time,　the　latest　research　results　of　PAI-1　inhibitors　in　the　field　of　anticancer　were　analyzed,　and　the　potential　application　value　of　PAI-1　inhibitors　was　demonstrated.　©　2019　Institute　of　Biophysics,Chinese　Academy　of　Sciences.　All　rights　reserved.