FAK (Focal Adhesion Kinase) is a key non-receptor tyrosine kinase encoded by the PTK2 gene, functioning as a central signaling hub for cell adhesion, migration and extracellular matrix signal transduction. Ubiquitously expressed in various cells and enriched at focal adhesion sites, FAK responds to cell-extracellular matrix adhesion signals and activates downstream signaling cascades including PI3K, ERK and Src via autophosphorylation, regulating cell adhesion, migration, proliferation, survival, invasion and cytoskeletal remodeling. Aberrant FAK activation and overexpression disrupt cellular adhesion homeostasis, promote tumor invasion, metastasis, malignant proliferation and drug resistance, and participate in tissue fibrosis and inflammatory repair disorders, making it a promising target for tumor targeted therapy.