The JAK/STAT signaling pathway plays a critical role in leukemia development, particularly in myeloproliferative neoplasms (MPNs). Over the past three decades, significant progress has been made in understanding the pathway's involvement in leukemia, with the discovery of the JAK2V617F mutation in MPNs being a key milestone. This mutation is associated with various hematological malignancies, including essential thrombocythemia (ET), polycythemia vera (PV), and primary myelofibrosis (PMF). The JAK/STAT pathway is involved in immune regulation, cell division, differentiation, and apoptosis, and its dysregulation contributes to leukemia progression. JAK/STAT inhibitors have emerged as promising therapeutic agents, with several FDA-approved drugs such as ruxolitinib, pacritinib, and fedratinib showing efficacy in treating MPNs and other leukemias. These inhibitors work by blocking JAK kinase activity, thereby inhibiting cytokine signaling and reducing leukemia cell proliferation. Additionally, STAT inhibitors are being explored for their potential in leukemia treatment, with some showing synergistic effects when combined with other therapies. Clinical trials have demonstrated the safety and efficacy of JAK/STAT inhibitors in various leukemia subtypes, although challenges remain in optimizing their use and understanding their mechanisms of action. Future research should focus on elucidating the complex regulatory mechanisms of the JAK/STAT pathway, exploring its interactions with other signaling pathways, and developing more targeted and effective therapies for leukemia patients.The JAK/STAT signaling pathway plays a critical role in leukemia development, particularly in myeloproliferative neoplasms (MPNs). Over the past three decades, significant progress has been made in understanding the pathway's involvement in leukemia, with the discovery of the JAK2V617F mutation in MPNs being a key milestone. This mutation is associated with various hematological malignancies, including essential thrombocythemia (ET), polycythemia vera (PV), and primary myelofibrosis (PMF). The JAK/STAT pathway is involved in immune regulation, cell division, differentiation, and apoptosis, and its dysregulation contributes to leukemia progression. JAK/STAT inhibitors have emerged as promising therapeutic agents, with several FDA-approved drugs such as ruxolitinib, pacritinib, and fedratinib showing efficacy in treating MPNs and other leukemias. These inhibitors work by blocking JAK kinase activity, thereby inhibiting cytokine signaling and reducing leukemia cell proliferation. Additionally, STAT inhibitors are being explored for their potential in leukemia treatment, with some showing synergistic effects when combined with other therapies. Clinical trials have demonstrated the safety and efficacy of JAK/STAT inhibitors in various leukemia subtypes, although challenges remain in optimizing their use and understanding their mechanisms of action. Future research should focus on elucidating the complex regulatory mechanisms of the JAK/STAT pathway, exploring its interactions with other signaling pathways, and developing more targeted and effective therapies for leukemia patients.