Background: Tumor phenotypes are dictated not only by the neoplastic cell component, but also by the tumor microenvironment (TME), which includes immune and inflammatory cells. We characterized the immune ecosystem of the bone marrow (BM) TME in patients with acute myeloid leukemia (AML) to correlate transcriptomic and proteomic profiles with patient outcome. Methods: We used the nCounter system (NanoString Technologies) to characterize BM specimens from 42 children and 28 adults with AML. Ninety BM samples (63 from de novo AML, 18 from AML in complete remission [CR] and 9 from relapsed AML) were analyzed using the RNA Pan-Cancer Immune Profiling Panel. In situ leukemia-immune system interactions were visualized using Digital Spatial Profiling (DSP). Results: Hierarchical clustering identified subgroups with heightened expression of lymphocyte-associated genes, including NK cell and cytotoxicity genes (“immune-enriched” samples). They also expressed CD8A, IFNG, FOXP3, the cell chemoattractants CXCL9, CXCL10, and inhibitory molecules including IDO1 and the immune checkpoints LAG3, CTLA4 and PD-L1. Conversely, ‘immune-depleted’ samples over-expressed genes associated with mast cell functions and CD8 T-cell exhaustion and showed low expression of T-cell and B-cell genes. Importantly, relapse-free survival (RFS) and overall survival (OS) were significantly shorter in patients with “immune-enriched” compared with “immune-depleted” AMLs (2.2 vs. 18.3 months, p = 0.0064, and 6.3 vs. 22.4 months, p = 0.017, respectively). DSP of the BM TME showed the co-localization of CD8 T cells with FoxP3 Treg cells and PD-L1- and VISTA-expressing cell types, an immune landscape which is consistent with the establishment of adaptive immune resistance mechanisms of immune escape. Conclusions: Our study has identified heterogeneous immune profiles in children and adults with AML. From a clinical standpoint, ‘immune enriched’ AMLs might be amenable to immunotherapy approaches tailored to the BM microenvironment, including blockade of co-inhibitory molecules and/or small-molecule IDO1 inhibitors. Grant support: Roger Counter Foundation, UK; Qatar National Research Fund (#NPRP8-2297-3-494).