The glycoprotein Reelin is essential for neuronal migration during embryonic development and is involved in various cellular processes. It interacts with specific lipoprotein receptors to regulate neuronal migration and synaptic plasticity. Recent research has expanded our understanding of Reelin's functions, revealing its involvement in processes such as cell proliferation, activation, migration, platelet aggregation, and vascular development. Reelin's influence extends beyond neurodevelopment, with abnormal expression observed in several cancer types. This suggests a potential connection between Reelin dysregulation and tumor formation. Altered Reelin levels correlate with increased tumor aggressiveness, metastatic potential, and poor patient outcomes. In cancer, Reelin affects key cellular processes including proliferation, migration, and invasion. Evidence indicates that Reelin modulates important signaling pathways like PI3K/Akt and MAPK, contributing to the development of cancer hallmarks. Its interactions with integrins and matrix metalloproteinases imply a role in shaping the tumor microenvironment, thereby influencing cancer progression. These findings highlight Reelin's dual significance in neurodevelopment and cancer biology. Further investigation into Reelin's complex functions could lead to new diagnostic tools and therapeutic approaches, potentially advancing cancer treatment through targeted research on its signaling mechanisms. This review provides a condensed overview of Reelin's multifaceted roles in both neurodevelopment and cancer.