The present study was designed to investigate the influence of vacuum packaging on chemical and microbial parameters of beef during frozen and refrigeration storage. Quality assessment of vacuum packaged beef up to 10 weeks was done by the monitoring of quality, TVB-N, free fatty acids (FFA), thiobarbituric acid (TBA), Histamine, pH and some bacterial count such as Enterobacteriaceae count,Psychrotrophic counts,Mesophilic count and lactic acid bacteria. A total of 100 fresh beef samples,20 samples of them were examined biochemically and bacteriologically on zero day before starting the experiment and the rest of 80 samples were divided into two main groups, 40 samples each. First main group divided into two subgroups, 20 samples each. First subgroup (A) stored in freezer without vacuum packaging for ten weeks at -18°C. The second subgroup (A) were vacuumed byVacsy system and kept in freezer for ten weeks at -18°C. The second main group was divided into two subgroup, 20 samples each. First subgroup (B) stored on shelf of refrigerator without vacuum packaging for 5 days at 4°C. The second subgroup(B) were vacuumed by Vacsy system and stored in cyst of vacuum then all samples of the second main group were kept on shelf of refrigerator for 5 days at 4°C. 4 samples were taken from each subgroup of the first main group (A) every two weeks until the end of the experiment(ten weeks),also 4 samples were taken from the second main group (B) daily for 5 days (4 samples from each subgroup) and subjected to biochemical and bacteriological examination. Obtained results showed that TVB-N, (FFA), (TBA), Histamine and pH values of vacuum packaging samples were significantly lower than those in non-vacuum packaging samples. Results indicated that vacuum packaging was effective in reduce lipid oxidation and increased shelf life of beef. Similarly the microbial load of vacuum packaging samples were significantly lower as compared to non-vacuum packaging samples. Results also indicated that vacuum packaging had a very good effect on the organoleptic properties such as color, odor and taste during refrigeration, but their was no clear effect during freezing period on the organoleptic properties. Thus, the employment of vacuum packaging alone or in combination with other protective strategies is recommended