Because medicinal plants contain bioactive phenolic compounds with antibacterial, antioxidant, and other properties, they have been used in many parts of nutrition and healthcare. The atmosphere in which local meat products and vendors operate is still subpar. Every individual is impacted, either directly or indirectly, when food is contaminated by harmful germs and spoilage. In this study, the microbiological purity, preservation, and shelf life of beef meat were assessed. The study analyzed the bacterial count in beef burger and luncheon samples, with gram negative bacteria having the highest contamination rate (58%). Four selected bacteria isolates were identified based on their morphological and cultural characteristics, confirmed by VITEK 2 system analysis and were identified as bacterial isolates from the Bacillaceae, Enterobacteriaceae, Pseudomonadaceae, and Staphylococcaceae families. The study found nine active compounds in rosemary leaves extract, including ferruginol, camphor, cineole, verbenone, borneol, αcaryophyllene, terpinen-4-ol, 2-methyl-4-vinylphenol, and eugenol, which act as antioxidants and antibacterials. The aqueous rosemary leaves extract (ARLE) showed efficacy in antibacterial activity against various bacteria, with clear inhibition zones (CIZ) and mean growth inhibition (MGI) values of 28.1 mm and 37%, respectively. The addition of ARLE to meat beef significantly reduced counts of pathogenic bacteria during storage. The preservation effectiveness of ARLE against artificially inoculated Staphylococcus aureus and Pseudomonas aeruginosa in meat beef exhibited complete bactericidal effect, with no recovery of the pathogen. The study assessed the impact of ARLE on meat beef sensory quality, finding that at a concentration of 15 mg/g, ARLE did not affect overall acceptability but enhanced the meat's sensory properties. When used as a natural antioxidant agent, the ARLE's antioxidant activity through DPPH scavenging proved to be successful in food preservation. Its radical-scavenging activity increased with concentration, with high DPPH radical-scavenging activity at 2560 μg/mL and varying percentages at different concentrations. ARLE also showed cytotoxicity against colon carcinoma cells (HCT-116), breast carcinoma cells (MCF-7), and human hepatocellular carcinoma cells (HepG-2) for 24 h. Applying ARLE significantly extended meat shelf-life by reducing microbial counts and inhibiting pathogens. To strengthen this conclusion, referencing specific safety and spoilage thresholds, such as TVC below 10 CFU/g, would provide a clearer, quantitative assessment of preservation. Demonstrating that treated samples remained below these limits longer than controls would offer concrete evidence of practical shelf-life extension.