Abstract: This study focused on isolating Heyndrickxia coagulans strains with robust anti-Helicobacter pylori activity and assessing their synergistic potential in fermented milk production. Thirteen H. coagulans strains were successfully isolated from traditional fermented foods, including homemade soybean paste, douchi, and sauerkraut, through a combination of plate separation, Gram staining, morphological characterization, and 16S rDNA sequencing. Flow cytometry-based inhibition assays against H. pylori SS1 revealed seven strains with growth suppression rates exceeding 80%, with strains A1 and E26 exhibiting the highest efficacy. Their 48 h-fermented supernatants achieved remarkable inhibition rates of 98.24% and 90.35%, respectively, demonstrating significant therapeutic potential against this gastric pathogen. To evaluate their industrial applicability, A1 and E26 were co-fermented with a conventional dairy starter culture (Streptococcus thermophilus and Lactobacillus delbrueckii subsp. bulgaricus, designated as BS). The co-fermented groups (A1+BS and E26+BS) displayed accelerated acidification kinetics, reaching pH 5 within 6 h—2 h faster than the BS-only control—and achieved final pH values of 4.51 and 4.55, alongside titratable acidity levels of 80.82 °T and 78.71 °T. Textural analysis indicated favorable water-holding capacities of 39.53% and 38.67% for A1+BS and E26+BS, respectively, suggesting enhanced structural stability. Microrheological assessments, including elasticity and viscosity profiles, as well as sensory evaluations of flavor, texture, and overall acceptability, showed no significant differences between co-fermented and traditional BS groups, confirming that the inclusion of H. coagulans did not compromise product quality. These findings underscore the dual functionality of H. coagulans A1 and E26 as both potent anti-pathogenic agents and fermentation accelerators. Their compatibility with conventional starters, ability to shorten production timelines, and retention of sensory attributes position them as innovative candidates for functional dairy products. This research advances the integration of probiotic strains into food biotechnology, offering a strategic approach to developing therapeutic fermented foods while addressing industrial demands for efficiency and consumer preferences for natural, health-promoting ingredients.