Pericytes are contractile mural cells. Studies have highlighted an important contribution of pericytes to the tissue micro-environment (blood-brain-barrier integrity and permeability), trans-vascular migration of immune cells and spinal cord repair. Adding to this, the present study suggests that pericytes are also key players in the micro-environment and function of pituitary cell networks. Together with the emerging microvasculature, pericytes from two embryological origin (neural crest and mesodermal) invade the pituitary from E14.5; modifying during postnatal days its morphology and capillary association until in adult mice they are then located both along the capillaries and within the parenchyma, making anatomical bridges between capillaries. Organization of neural crest (NC)-derived pericytes form a rostro-caudal gradient, mostly on the ventral side of the pituitary. NC-derived pericyte functioning was explored by using both cellular in vivo imaging and optogenetic tools. Pituitary pericytes can control blood vessel dynamics, partial oxygen pressure and hormone outputs. These data suggest that pericytes are multitask cells of the pituitary microenvironment.