Migration of postmitotic neurons in the developing cortex along radial glial fiber is essential for the formation of cortical layers.Several neurological diseases are caused by defects in neuronal migration, underlining the importance of this process for brain function.Multiple molecules are involved in this process.However, the precise mechanisms are largely unknown.In the present study, we examined the expression of Src in developing cortex and investigated the role of Src in neuronal migration and its cellular and molecular mechanism.Our results showed that Src was strongly expressed in cerebral cortex during corticogenesis and mainly targeted to the leading process in migrating neurons.Overexpression of wildtype Src (Src-WT) and its mutants, constitutively active Src (Src-CA) and dominant negative Src (Src-DN) in mouse brain by in utero electroporation perturbs the neuronal migration through affecting the adhesion property and cytoskeletal dynamics of migrating neurons.Overexpression of Src-WT and Src-CA induces aggregation and branching of migrating neurons, whereas overexpression of Src-DN leads to abnormal elongation of leading process of migrating neurons.Furthermore, we showed that Src activates the Focal adhesion kinase (FAK) and cofilin by regulating their phosphorylation levels.We conclude that Src controls neuronal migration by regulating adhesion property and F-actin dynamics of migrating neurons.