Ethanolamine-grafted graphene quantum dots (ETAM-GQDs) as a novel type of carbon-based quantum dots have been successfully synthesized via a facile one-pot hydrothermal approach，and show potential application in bioimaging.The hydrothermal synthesis of ETAM-GQDs was accomplished by introducing ethanolamine (ETAM) as the co-solvent blending deionized water while citric acid and glycine are used as the main carbon source and bridge for condensation respectively. The size distribution of ETAM-GQDs was determined by AFM and TEM. The photoluminescent (PL) quantum yield of ETAM-GQDs was measured to be 38.2% under 365 nm light excitation by using quinine sulphate as a standard. The biocompatibility of ETAM-GQDs evaluated by MTT assay indicated the low toxicity of ETAM-GQDs at concentrations below 1 mg/mL. Fluorescent imaging of living HL7702 cells incubated with ETAM-GQDs demonstrated that ETAM-GQDs can be applied as an effective bioimaging agent.