A new fluorescence method for the determination of trace Cu2+was developed by using fluorescence resonance energy transfer between carbon quantum dots and fluorescent pink，in which carbon dots acted as an energy donor and FP as an acceptor.It was found that under the conditions of λex=581 nm and pH=8.4 aqueous solution，energy transfered from carbon dots to FP and led to enhance the fluorescence of FP.However,the addition of trace Cu2+made FP fluorescence quenching.The quenching degree was quantitatively in proportion to the trace Cu2+content.Therefore，a novel fluorescence quenching platform for determination of trace Cu2+was constructed.Under the optimum conditions，the calibration curve for Cu2+concentration was linear in the range of 9.42-23.55 μmol/L with a detection limit(3σ/k) of 3.14 μmol/L.The method was applied in the determination of trace Cu2+in river，farmland water and tap water，with spiked recoveries of 98.7%-99.0% and relative standard deviations(RSD) not more than 0.91%.