〔Abstract〕 Objective To investigate the interaction between intracellular chloride ion protein 1(CLIC1) and activated protein kinase C receptor 1(RACK1). Methods Plasmids pcDNA3.1-RACK1-HA and/or pcDNA3.1-CLIC1-FLAG were transfected into HEK 293 T cells, and pcDNA3.1-RACK1-HA and/or pcDNA3.1-CLIC1-FLAG were transfected into COS7. GST-pulldown and immunoprecipitation assays were performed to determine the interaction between CLIC1 and RACK1in vivoandin vitro. The co-localization of CLIC1 and RACK1 was observed by indirect immunofluorescence assay. Results Western blot confirmed that CLIC1 and RACK1 could be highly expressed in HEK 293 T cells. GST-pulldown showed that RACK1 bound CLIC1in vitro, and immunoprecipitation showed that CLIC1 and RACK1 interactedin vivo. Furthermore, indirect immunofluorescence assay showed CLIC1 co-localized with RACK1. Conclusion Human CLIC1 protein interacts with RACK1in vitroandin vivo.