Metabolomics, an emerging discipline, analyzes the totality of metabolites in cells, tissues, and fluids, providing real--time insights into the metabolic state of an organism. Recent advances in technology and databases have driven research focused primarily on the pathophysiology of solid tumors. However, metabolomics is also gaining importance in hematopoietic neoplasms, particularly acute myeloid leukemia and multiple myeloma. This review discusses potential novel biomarkers for diagnosis, risk assessment, and treatment response in hematological cancers that offer promising prospects for personalized therapies.