The extracellular polysaccharide (EPS) from Lactobacillus plantarum plays important roles in the special texture and flavor of fermented dairy products. These EPSs possess biological activities such as immunomodulation, antitumor and regulating the balance of intestinal flora and so on, which can be used in food and medicine fields. However, the yield of Lactobacillus plantarum EPS is relatively low, factors affecting the EPS production are strain specific, and the influence of Lactobacillus plantarum EPS on the stability of the products is still rarely studied. The optimal fermentation conditions obtained by single factor experiments and response surface analysis were as follows:peptone 10g/L, yeast extract powder 5g/L, glucose 20g/L, potassium hydrogen phosphate 2.0g/L, anhydrous sodium acetate 5.0g/L, sodium citrate 5.0g/L, magnesium sulfate 0.2g/L, manganese sulfate 0.05g/L, twain 80 1.0mL/L, fermentation temperature 30℃, fermentation time 24h, and initial pH of culture medium of 6.5. The maximal production of EPS was 250.21mg/L under the above conditions. The results of rheological characteristics studies indicated that the EPS aqueous solution exhibited the increased viscosity as the concentration of the EPS and the share rate increased, and shear thickening properties. The scanning electron microscopy verified the cuboid microstructure of the EPS molecules, facilitating stabilization of the texture and water retention in solution. Application of this EPS for preparation of acid milk beverage showed that the use of the EPS could improve stability of the beverage, indicating that the EPS from Lactobacillus plantarum K25 can be potentially used as a novel food stabilizer.