Myeloid malignancies are composed of multiple clonal hematopoietic disorders, including myelodysplastic syndrome, myeloproliferative neoplasms, and acute myeloid leukemia. Inflammation is already known to play an important role in the pathogenesis of an extensive variety of malignancies, and its significance in myeloid malignancies is becoming more widely recognized. Specifically, cell-intrinsic and -extrinsic activation of the innate immune signaling pathway, as well as elevation of proinflammatory cytokines via innate immune signaling downstream signaling, have been demonstrated. Furthermore, the inflammatory microenvironment refers to the bone marrow environment rich in inflammatory signaling molecules that surround hematopoietic malignant cells, and its role in the pathogenesis of myeloid malignancies has been extensively studied in recent years. Herein, we present the latest findings and discuss how innate immune signaling activation and the inflammatory bone marrow microenvironment contribute to the pathogenesis of myeloid malignancies.