In this paper,the water soluble copper-silver nanoclusters（Cu-AgNCs）with red fluorescence were prepared by one step method with D penicillamine as ligand under mild conditions.The morphology,structure and fluorescence properties were characterized.Result showed that the quantum yield of the prepared nanoclusters reached up to 96%,and there was a good linear relationship between fluorescence intensity and temperature of the nanocluster in the range of 279-355 K.With the increase of temperature,the fluorescence intensity decreased.In addition,the results of MTT experiments showed that as the synthesized Cu-AgNCs exhibited a low toxicity and a good biocompatibility,they could permeate into E.coli cells,and enable measurements over the physiological temperature range of 293-313 K with the use of the confocal fluorescence imaging method.The results showed that the prepared Cu-AgNCs were expectable to use as a photoluminescence thermometer and biosensor in fluorescence imaging and other fields.