Dendritic cells orchestrate the crosstalk between innate and adaptive immunity. CD8 alpha(+) dendritic cells present antigens to CD8(+) T cells and elicit cytotoxic T cell responses to viruses, bacteria and tumours(1). Although lineage-specific transcriptional regulators of CD8 alpha(+) dendritic cell development have been identified(2), the molecular pathways that selectively orchestrate CD8 alpha(+) dendritic cell function remain elusive. Moreover, metabolic reprogramming is important for dendritic cell development and activation(3,4), but metabolic dependence and regulation of dendritic cell subsets are largely uncharacterized. Here we use a data-driven systems biology algorithm (NetBID) to identify a role of the Hippo pathway kinases Mst1 and Mst2 (Mst1/2) in selectively programming CD8 alpha(+) dendritic cell function and metabolism. Our NetBID analysis reveals a marked enrichment of the activities of Hippo pathway kinases in CD8 alpha(+) dendritic cells relative to CD8 alpha-dendritic cells. Dendritic cell-specific deletion of Mst1/2-but not Lats1 and Lats2 (Lats1/2) or Yap and Taz (Yap/Taz), which mediate canonical Hippo signalling-disrupts homeostasis and function of CD8(+) T cells and anti-tumour immunity. Mst1/2-deficient CD8 alpha(+) dendritic cells are impaired in presentation of extracellular proteins and cognate peptides to prime CD8(+) T cells, while CD8 alpha(+)-dendritic cells that lack Mst1/2 have largely normal function. Mechanistically, compared to CD8 alpha-adendritic cells, CD8a+ dendritic cells exhibit much stronger oxidative metabolism and critically depend on Mst1/2 signalling to maintain bioenergetic activities and mitochondrial dynamics for their functional capacities. Further, selective expression of IL-12 by CD8 alpha(+) dendritic cells depends on Mst1/2 and the crosstalk with non-canonical NF-kappa B signalling. Our findings identify Mst1/2 as selective drivers of CD8 alpha(+) dendritic cell function by integrating metabolic activity and cytokine signalling, and highlight that the interplay between immune signalling and metabolic reprogramming underlies the unique functions of dendritic cell subsets.