Blood disorders include a wide spectrum of blood-associated malignancies resulting from inherited or acquired defects. The ineffectiveness of existing therapies against blood disorders arises from different reasons, one of which is drug resistance, so different types of leukemia may show different responses to treatment. Leukemia occurs for a variety of genetic and acquired reasons, leading to uncontrolled proliferation in one or more cell lines. Regarding the genetic defects, oncogene signal transducer and activator of transcription (STAT) family transcription factor, especially STAT3, play an essential role in hematological disorders onset and progress upon mutations, dysfunction, or hyperactivity. Besides, microRNAs, as biological molecules, has been shown to play a dual role in either tumorigenesis and tumor suppression in various cancers. Besides, a strong association between STAT3 and miRNA has been reported. For example, miRNAs can regulate STAT3 via targeting its upstream mediators such as IL6, IL9, and JAKs or directly binding to the STAT3 gene. On the other hand, STAT3 can regulate miRNAs. In this review study, we aimed to determine the role of either microRNAs and STAT3 along with their effect on one another's activity and function in hematological malignancies.