In the past decades, platinum (Pt) is employed to clinical treatment of various cancers. However, for Pt based drugs, especially Pt in +2 state [Pt (II)], such as cisplatin, number of drawbacks impede their anticancer efficiency including poor pharmacology, fast blood clearance, systemic toxicities causing from poor specificity and excretion of drug through kidneys. Herein, we developed dual-functional ultrafine polyethylenimine caged platinum nanoclusters (PEI-caged Pt NCs), which were utilized in biological imaging of the suspension cells system as fluorescent markers, and selective inhibition of hematopoietic malignancies as anticancer chemotherapeutics simultaneously. These zerovalent Pt NCs are capable to selectively enter into blood cancer cells (K562, BV173 cell lines) when compared to the peripheral blood mononucleated cells (PBMCs) from healthy donors, in addition, it can specifically induce pro-apoptotic protein expression (p53, PUMA, cleaved caspase) in hematopoietic cancer cells and promote cell apoptosis. Avoiding the adding of other fluorescent bio-markers, these Pt NCs showed great potential in diagnosis and treatment of hematopoietic system disease, such as acute myeloid leukemia, lymphoma, myeloma, etc. (C) 2018 Elsevier Inc. All rights reserved.