Lactic acid bacteria (LAB) have long been used in Asian culture as a preservative and value added method for food processing. Mekong Delta (MD) is the main agricultural area of Vietnam with rich sources of fruits and starch-based products which can be ultilized for lactate fermentation. The aims of the study were to isolate thermotolerant LAB in MD, to investigate the properties and to ultilize the thermotolerant LAB in different applications. As a result, 54 Strains of LAB were isolated in MD, Vietnam in which 16 strains could produce high lactic acid content (0.9-1.65 g/L) in 4% sucrose minimal medium. The strains were belonged to Lactobacillus genus. Among them, L. casei L9 could produce 28.35 g/L lactic acid  with 75.37% efficiency in 5 days. Besides, L. casei L9 could ferment sugarcane molasses and pineapple peel extract to produce 13.48 and 17.63 g/L acid content. Tofu sour liquid could be ultilized as growth medium for lower cost. Moreover, L. plantarum L54 showed high antibacterial properties against Bacillus subtilis, Micrococcus luteus and L. casei. Tofu sour liquid could be ultilized as growth medium as low cost that could produce 1.69 g/L cell biomass in 20L scale. The promising results indicated the newly strains of lactic acid bacteria could be applied in practical production.