Objective To develop a method combining surface-enhanced Raman scattering (SERS) spectrum and electrostatic adsorption for detecting circulating tumor cells. Methods Graphene oxide was non-covalently functionalized by poly(sodium-p-styrenesulfonate) (PSS), and graphene oxide/gold nanorod (GO/GNR) hybrids were in situ synthesized via gold seeding growth approach. Then, GO/GNR hybrids were non-covalently functionalized by poly dimethyl diallyl ammonium chloride (PDDAC) to make the surface of GO/GNR positively charged. GO/GNR hybrids would target the tumor cells by electrostatic interaction. SERS technology was used to detect the composites of GO/GNR-tumor cells. The blood samples of healthy volunteers were collected, and the tumor cells of different densities were added to the blood samples to make simulated blood samples. The tumor cells in simulated blood samples were detected using the above methods. Results Positively charged GO/GNR hybrids could efficiently target the tumor cells. SERS spectroscopy could detect tumor cells within 50 to 10 000 cells. However, white blood cells might interfere the detection of tumor cells. Conclusion GO/GNR hybrids may serve as SERS probes for detection of circulating tumor cells via Raman spectroscopy.