Quality aspects of sliced dry-cured beef "Cecina de León" preserved in vacuum and gas mixtures (20%/80% CO(2)/N(2) and 80%/20% CO(2)/N(2)) were studied. The evolution of microbiological, physicochemical and sensory parameters were analysed during storage (210 days) at 6°C. Although microbial counts at 60 days of the gas-packaged samples were lower than the vacuum-packed ones, they were never higher than the spoilage limit (7 logufc/g). A slight increase (p<0.05) in pH was observed throughout storage of "Cecina de León" packaged under vacuum and in gas mixtures. However, a decrease (p<0.05) in a(w) was observed during storage of "Cecina de León" packaged under vacuum but a(w) did not vary (p>0.05) during storage in the gas-packaged samples. No changes were observed (p>0.05) in lightness (L(∗)), redness (a(∗)) and yellowness (b(∗)) in vacuum and gas packaged samples during storage. However, sensorially evaluated colour showed lower values in gas packaged samples during 30 days storage. This difference was decisive in establishing the shelf-life of "Cecina de León" slices preserved in gas mixtures (20%/80% CO(2)/N(2) and 80%/20% CO(2)/N(2)). Therefore, from a microbiological point of view, gas mixtures are more effective in extending the shelf-life of "Cecina de León" slices. It is concluded that vacuum packaging allows longer storage than gas-packaging as it maintains a good visual appearance of "Cecina de León", the main parameter in consumers' perception of meat quality.