Objective To investigate the contamination status of foods by L. monocytogenes. Method In the summer months of recant years, 3 586 food samples of 6 kinds of chilled and frozen foods were collected from supermarkets in Zhuhai and examined for L. monocytogenes PCR was applied first to detect Listeria in food samples, and then the national standard method, GB/T 4789.30-2003, was used to validate the positive results. Results The results showed that there were heavy contamination of foods by Listeria in Zhuhai, and there existed multiple contamination. Raw fresh milk, raw meat, poultry and vegetables had high contamination rates of both Listeria and L. monocytogens. Conclusion Inspection and management of chilled and frozen foods should be enhanced to prevent Listeria infection.