most cells in the brain are formed during embryonic development, where neural stern/progenitor cells (NSPCs) divide to generate new NSPCs, neurons and glial cells. NSPCs persist throughout adulthood in some regions and continually generate new neurons in a process called adult neurogenesis. Lipid metabolism is important for NSPCs, as they rely on fatty acid oxidation (FAO) and de nova lipogenesis for proper maintenance and proliferation. Lipid droplets (LDS) are lipid storing organelles and have a key function in lipid metabolism: they store neutral lipids, either taken up or newly generated from de nova lipogenesis, and are an important lipid reservoir for FAO. We show that LDS are abundant in proliferating and quescent adult NSPCs in vitro, and we also show that LDS upon division and inhibition of LD build-up and breaking down concerns NSPC proliferation. Moreover, LDS changes when NSPCs are treated into astrocytes and neurons in vitro. LDS were found in the healthy brain, maintained in ependymal cells along the ventricles and in glial cells during brain development. However, they have been shown to Accumulate in neurons and glial cells upon disease. Many of these studies on classified approaches, making it it dependent to study the dynamics of LDS. We thefore generated an Endogenous LD report moving by tagging the LD marker, PLIN2 with the fluorophore tdTomato. This allows for detection of LDS in a staining free manner, in both tissue and cells. We have, using this LD report, shown that 4 % of the cells in the mouse brain have LDS. LDS are found in ependymal cells, microglia, endothelial cells, neurons, astrocytes and NSPC. Moreover, LDS are abundant during embryonic brain development, and LDS in acute embryonic brains can be imaged live and react DYNAMICALLY to external lipids. Furthermore, we exposed the reporter to a high fat diet to investigate how nutrition influences the LDS in the brain. Taken together, this novel reporter mouse is a useful tool for studying LDS in the mouse brain. It releases us the opportunity to investigate if our in vitro findings in NSPCs holds true in vivo and, as PLIN2 is ubiquitous expressly, this musse also allows for studying LDS in other organs. — Most brain cells are formed during embryonic development, where neural stem/progenital cells (NSCs) are divided to generate new CSPN, neurons and glial cells. NCPs persist until adulthood in some regions and generate new neurons in a process called adult neurogenesis. Lipid metabolism is important for NCPs as they depend on fatty acid oxidation and novo lipogenesis for survival. Lipid droplets (GL) are lipid storage organisations and have a key function in lipid metabolism: they store the lipids newly synthesised by novo lipogenesis and constitute an important lipid reservoir for the oxidation of fatty acids. Here, we show that GLs are abundant in adult in proliferating and quiescent mice NCPs in vitro. We also show that the legacy of GL in cell division and the inhibition of their accumulation and degradation affect the proliferation of NCPs. Moreover, the GLs change when the NCPs are differentiated into astrocytes and in vitro neurones. In the brain, GL are mainly present in eppendymer cells along the ventricules and in glial cells during development. However, it has been shown that they also accumulate in neurons and glial cells in case of pathology. Most of these studies are based on traditional colouring approaches, which makes it difficult to study the dynamics of GL. We therefore generated a mice rapporteur of the endogenous GLs by adding fluorophore tdTomato to the GL PLIN2 marker. This allows the detection of non-staining GLs, both in tissues and cells. Using this mouse, we have shown that 4 % of the cells in the mouse brain have GL. GLs are present in eppendymayor cells, microglie, endothelial cells, neurons, astrocytes and CSPN. Moreover, the GLs are abundant during the development of the embryonic brain, and can be imagined in real time in acute slices, reacting dynamically to external lipids. In addition, we exposed our mice to a fat rich diet to study the influence of nutrition on the GL of the brain. In summary, this reporting mouse is a useful tool to study GL in the mouse brain. It will make it possible to check whether our in vitro results in CSPNs are verified in vivo, as well as to study GLs in other organs, since PLIN2 is expressed ubiquitously.