This study was carried out on 90 imported frozen samples of meat and mackerel fish (45 each). These samples were obtained from different shops and markets of varied sanitary levels at Assuit city. Listeria species were isolated from 35.6% of frozen meat and 57.8%of frozen mackerel fish with an average counts of 3.2×10³ and 11.3×10⁴ /g respectively. Listeria monocytogenes was differentially identified from other Listeria species and could be isolated at variable percentages 17.8% and 13.3% in the imported frozen meat and mackerel fish samples. The study revealed that the incidence of Listeria monocytogenes was higher in imported frozen meat as compared to frozen mackerel fish. Antibiogram for the. Listeria monocytogenes revealed that the isolates were susceptible (100%) to norfloxacin and chloramphenicol and showed different degrees of antimicrobial sensitivity reactions for rifampin, tetracycline, cefadroxil, cefataxime and streptomycin while all isolates (100%) were resistant to ampicillin, rimactan, garamycin and kanamycin. The hygienic and public health importance of the isolated organisms were discussed.