A total of 15 food-grade Lactobacillus strains were evaluated for their antagonism against gastrointestinal pathogens using Bifidobacterium animalis subsp. lactis BB-12 as a control. The results showed that nine of the strains possessed excellent antibacterial properties against five indicator bacteria tested, and two of the remaining six strains were antagonistic against four of the indicator bacteria, Staphylococcus aureus, Salmonella, E. coli and Bacillus cereus. According to their antagonistic effect, acid producing ability and milk curding ability, four strains were selected and each of them was combined with Streptococcus thermophilus ST-21 for use as bio-preservative starter cultures. Streptococcus thermophilus ST-21 + strain Z-38 at a ratio of 2:1 could produce acid rapidly, have potent post-acidification capacity and produce a strong milky aroma, being suitable for the production of flavored yogurt. Streptococcus thermophilus ST-21 + strain Z-40 at a ratio of 2:1 resulted in the best texture of yogurt, being suitable for the production of fermented dairy drink. Yogurt fermented by Streptococcus thermophilus ST-21 + strain Z-12 at a ratio of 1:1 showed the lowest consistency and cohesiveness.