Quantum dots (QDs) or nanocrystals 5 to 50 nm in size have recently emerged as a novel and promising class of fluorophores for cellular imaging. Unlike conventional organic dyes, QDs can be excited by a wide spectrum of wavelengths to give enhanced photostability, and their emission spectra, which differ according to size and material composition, are narrow, symmetrical, and tunable. This novel detection strategy can significantly improve the efficiency of molecular techniques used in the identification of important microbes related to human diseases. The aim of this study was to apply QDs linked antibodies to detect pathogenic Salmonella typhimurium cells. The signal, photostabilty and efficiency of QDs linked antibodies was compared with the organic fluorophore linked antibody for the detection of Salmonella cells. The use of QDs as fluorophores has shown greater enhancement in photostability and brighter signal than conven-tional organic dyes in detecting S. typhimurium cells. This approach might also be extended for the simultaneous detection of more than one pathogenic microorganism in the clinical, food or environmental samples by using specific antibodies linked with the QDs of different sizes and colors