In the laboratory diagnosis of hematological neoplasms based on the WHO classification, molecular-genetic testing is indispensable. Emerging technologies for such testing have resulted in a shift of the assay platform from the first generation of a single target for detection or quantitation into advanced multiplex analysis, digital image analysis, automation of measurement, and combination with immunophenotypic analysis. The multiplex assay has expanded its platform application to genome-wide analysis, such as array comparative genome hybridization, SNP array, and next-generation sequencers. These have been applied for the diagnosis of hematopoietic neoplasms, enabling whole-genome profiling of diseases. The application of genome-wide analysis, such as target sequencing, is expected to be a practical tool in the laboratory diagnosis of hematopoietic neoplasms. The clinical use of these emerging technologies would provide a molecular basis for the WHO classification of hematological neoplasms and, thus, promote the quality of treatment based on laboratory diagnosis.