<p>This study investigated the effect of a biodegradable edible coating based on Qodume Shahri mucilage and a <i>Limosilactobacillus reuteri</i> VTC 864 postbiotic on the quality and shelf life of fresh beef during 4^∘C storage. The results showed that all chemical spoilage indicators, including peroxide value (PV), thiobarbituric acid (TBA), and total volatile elemental nitrogen (TVB-N), increased over the storage period; however, the rate of increase was lower in coated samples, particularly in the combined treatment (<i>p</i> &lt; 0.05). Additionally, pH and moisture content remained more stable in coated samples, and the decline in texture hardness was slower in these treatments. Color parameters (<i>L</i>*, <i>a</i>*, and <i>b</i>*) were also better preserved in coated samples, minimizing color changes. Regarding microbial indices, the growth of total viable count (TVC), psychrotrophic bacteria count (PTC), fungi, and Enterobacteriaceae was significantly inhibited in coated samples, especially in the combined treatment, with TVC remaining below the microbial spoilage threshold on day 10. Sensory evaluation indicated higher scores for odor, color, and overall acceptability in coated samples, with the decline in sensory attributes being slower in the combined treatment compared to other groups. Overall, the results of this study demonstrated that using a combined Qodume Shahri mucilage postbiotic coating can simultaneously improve the chemical, microbial, physical, and sensory characteristics of red meat and significantly extend its shelf life under refrigerated storage. Based on these findings, the combined edible coating of Qodume Shahri mucilage and <i>L. reuteri</i> VTC 864 postbiotic can be considered a novel and natural approach to enhance the shelf life and quality of fresh beef.</p>