Background: Biological sex differences play a critical role in vascular diseases. Using endothelial ( EC ) lineage tracing atherosclerotic mice and cultured mouse and human aortic EC, we recently found that female EC have lower angiogenic potential, higher expression of pro-inflammatory genes and intracellular ROS, and worse mitochondria functions than male EC. However, the mechanisms responsible for this EC sexual dimorphism are still unknown. We previously identified the pluripotency factor OCT4 as a critical regulator of EC characteristics, including angiogenic potential, ROS accumulation, and mitochondrial functions. Therefore, this study aimed to test whether OCT4 is responsible for sex-dependent differences in EC in vivo and in vitro . Methods: We used male and female EC-specific tamoxifen-inducible OCT4 knockout and EC-lineage tracing (EC-OCT4 KO) mice to study the role of OCT4 in non-atherosclerotic conditions leading to pro-inflammatory angiogenesis, such as hind-limb ischemia and skin injury models. Male and female mouse aortic EC (MAEC) were isolated from EC-OCT4 KO and wild-type littermate mice for in vitro experiments. We performed BrdU assay, EC tube formation in Matrigel (in vitro angiogenesis), wound scratch assay, and angiogenic proteome profile array to evaluate angiogenic potential. Results: Compared to wild-type mice, EC-OCT4 KO male mice exhibited accelerated blood flow recovery and wound healing after hind-limb ischemia and skin injury. However, EC-OCT4 KO female mice showed no difference in blood flow recovery and delayed skin wound healing compared to control mice. In vitro , although male and female OCT4-KO MAEC had higher angiogenic potential than control, the phenotype in female EC was less pronounced. Mechanistically, we found that male OCT4 KO MAEC express higher levels of monocyte cytokine protein 1 ( MCP1 ). Furthermore, the inhibition of MCP1 in male OCT4 KO MAEC, but not in female cells, led to significant decreases in cell migration, proliferation, and endothelial tube formation in Matrigel. Conclusions: Our data indicate that OCT4-dependent mechanisms contribute to the sex differences observed in EC, suggesting a novel biological role for pluripotency signaling in vascular pathologies and homeostasis.