Mitochondria are dynamic organelles that play essential roles in cell functions such as apoptosis, cell cycle control, and ATP production. Their morphology changes in response to cellular conditions, shifting between fragmented and tubular network-like structures through coordinated fusion and fission. This study shows that during nutrient starvation, mitochondria become elongated and interconnected. This morphological shift depends on the type of starvation, with additive effects observed when multiple nutrients are depleted. The elongation is mediated by the downregulation of dynamin-related protein 1 (Drp1) through modulation of two Drp1 phosphorylation sites, leading to unopposed mitochondrial fusion. This mitochondrial tubulation protects mitochondria from autophagosomal degradation, allowing them to maximize energy production and supply autophagosomal membranes during starvation. The study demonstrates that mitochondrial elongation is induced shortly after starvation and is reversible. It is specifically triggered by the depletion of glutamine and/or amino acids, with faster and more extensive tubulation upon additional depletion of glucose and serum. The elongation is mediated by the downregulation of Drp1, leading to unopposed mitochondrial fusion. The mitochondrial elongation response is further shown to protect mitochondria from autophagic turnover under starvation conditions. This ability of autophagosomes to exclude mitochondria from autophagic sequestration during starvation may serve to provide efficient aerobic ATP production when energy sources are limited and also highlights the previously unappreciated substrate specificity of the autophagosomal pathway during nutrient deprivation. The study also shows that mitochondrial elongation is dependent on Mfn1 and Opa1, and is mediated by two Drp1 posttranslational modifications. The results indicate that Mfn1 is essential for starvation-driven mitochondrial tubulation, whereas Mfn2 is dispensable for this activity. The findings suggest that mitochondrial elongation serves a protective function from mitophagy, in agreement with previous studies. The study further shows that starvation-induced mitochondrial fusion prevents mitophagy, which may be due to the ability of elongated mitochondria to avoid degradation during the initial period of starvation. The results highlight the importance of mitochondrial morphology in cell survival during nutrient deprivation and suggest that mitochondrial elongation is a key mechanism for protecting mitochondria from autophagic degradation during starvation.Mitochondria are dynamic organelles that play essential roles in cell functions such as apoptosis, cell cycle control, and ATP production. Their morphology changes in response to cellular conditions, shifting between fragmented and tubular network-like structures through coordinated fusion and fission. This study shows that during nutrient starvation, mitochondria become elongated and interconnected. This morphological shift depends on the type of starvation, with additive effects observed when multiple nutrients are depleted. The elongation is mediated by the downregulation of dynamin-related protein 1 (Drp1) through modulation of two Drp1 phosphorylation sites, leading to unopposed mitochondrial fusion. This mitochondrial tubulation protects mitochondria from autophagosomal degradation, allowing them to maximize energy production and supply autophagosomal membranes during starvation. The study demonstrates that mitochondrial elongation is induced shortly after starvation and is reversible. It is specifically triggered by the depletion of glutamine and/or amino acids, with faster and more extensive tubulation upon additional depletion of glucose and serum. The elongation is mediated by the downregulation of Drp1, leading to unopposed mitochondrial fusion. The mitochondrial elongation response is further shown to protect mitochondria from autophagic turnover under starvation conditions. This ability of autophagosomes to exclude mitochondria from autophagic sequestration during starvation may serve to provide efficient aerobic ATP production when energy sources are limited and also highlights the previously unappreciated substrate specificity of the autophagosomal pathway during nutrient deprivation. The study also shows that mitochondrial elongation is dependent on Mfn1 and Opa1, and is mediated by two Drp1 posttranslational modifications. The results indicate that Mfn1 is essential for starvation-driven mitochondrial tubulation, whereas Mfn2 is dispensable for this activity. The findings suggest that mitochondrial elongation serves a protective function from mitophagy, in agreement with previous studies. The study further shows that starvation-induced mitochondrial fusion prevents mitophagy, which may be due to the ability of elongated mitochondria to avoid degradation during the initial period of starvation. The results highlight the importance of mitochondrial morphology in cell survival during nutrient deprivation and suggest that mitochondrial elongation is a key mechanism for protecting mitochondria from autophagic degradation during starvation.