Abstract: JAK/STAT includes many types of cell factors. Growth factor signal transduction is an important pathway and widely participates in cell multiplication, differentiation, and immunity adjustment. Aberrant-activated JAK/STAT signaling pathway is involved in carcinogenesis. Recent studies demonstrated that abnormal expression and activation of STAT3 were found in lymphoma. Constitutive activation of STAT3 promotes development, invasion, and metastasis of cancer. AG490, a JAK2 inhibitor, can block the JAK/STAT3 signal pathway and reduce the pathway's downstream STAT3 expression. Several studies showed that AG490 can inhibit cell proliferation and promote apoptosis in lymphoma. AG490 combined with chemotherapy drugs could improve sensitivity. In our study, we reviewed the potential role of JAK/STAT signaling pathway and the blocker AG490 in lymphoma.