Listeria monocytogens can be found widely in nature. It can grow at refrigeration temperature, low pH, and high salt. The disease that it caused a fatality rate of 20% or higher makes L. monocytogens to be a famous foodborn pathogen. After a number of recent foodborn outbreaks, it has been demonstrated that this bacterium poses a significant health risk and has attracted the attention of the food safety professionals and public health officers. This thesis introduces the general characteristics of this bacterium, including its physiological and biochemical traits, virulent factors, infection routes, symptoms, therapy, and epidemiology. This thesis is also especially emphasized on the introduction and comparison of the differences, the advantages, as well as the disadvantages between the traditional and rapid diagnosis methods. According to the US FDA Bacterial Analytical Manual, the rapid tests had been classified into three classes: miniaturized biochemical kits, immunochemical kits, and genetic kits. The principles, formats, techniques, commercial products and its production companies of each diagnosis methods are also incorporated in this thesis. The advantages and disadvantages of these methods and their applications have been assessed. Finally, we also evaluated the market of the traditional methods being used and the rapid tests in the world, including the US, and European Union. In conclusion, the diagnosis of this important bacterium both by rapid methods or newly developed biochip and sensor will continue to grow in the future.