CRK antibodies are essential tools for studying the CRK family of adaptor proteins, which play pivotal roles in intracellular signaling. The CRK family includes two major isoforms, CRKI and CRKII, derived from alternative splicing of the *CRK* gene. These proteins contain SH2 (Src homology 2) and SH3 (Src homology 3) domains, enabling them to link tyrosine-phosphorylated receptors or docking proteins (via SH2) to downstream effectors (via SH3). CRK proteins facilitate signal transduction pathways regulating cell adhesion, migration, proliferation, and apoptosis, often interacting with key molecules like SOS, C3G, and DOCK180. Dysregulation of CRK signaling is implicated in cancer, inflammation, and fibrosis. For instance, CRK overexpression or hyperactivation correlates with tumor invasion, metastasis, and poor prognosis in cancers such as glioblastoma and lung adenocarcinoma. CRK antibodies are widely used in techniques like Western blotting, immunoprecipitation, and immunofluorescence to detect CRK expression, phosphorylation status (e.g., Tyr221 in CRKII), and protein interactions. Researchers also employ these antibodies to explore CRK's role in disease mechanisms and evaluate therapeutic strategies targeting CRK-mediated pathways. Specificity remains a critical consideration, as cross-reactivity with homologous proteins (e.g., CRKL) or splice variants may occur. Recent studies further highlight CRK's involvement in immune responses and metabolic disorders, expanding its biomedical relevance.