NOVELTY - Oligomerization preparation of -b-1,3-glucan oligosaccharide comprises subjecting thermal gel to acidolysis using -b-glucanase, performing enzymolysis, performing acidolysis for obtaining oligosaccharide solution, performing interception separation and concentration by an ultrafiltration membrane for obtaining beta-1,3-glucan oligosaccharide with polymerization degree of 4-15 DP.    USE - Method for oligomerization preparation of -b-1,3-glucan oligosaccharide (claimed) useful in disease-resistant vaccine of plant.    ADVANTAGE - The method uses a mixed method of mild enzymolysis and acidolysis for performing oligomerization of the thermal gel, such that the enzymolysis reaction can be conveniently controlled with a lower-temperature hydrolysis condition and without damaging the structure of the -b-1,3-glucan oligosaccharide. Energy consumption is saved. The whole production technique does not pollute the environment, and the cost is low.    DETAILED DESCRIPTION - Oligomerization preparation of -b-1,3-glucan oligosaccharide comprises subjecting thermal gel to acidolysis using -b-glucanase, performing enzymolysis, performing acidolysis for obtaining oligosaccharide solution, performing interception separation and concentration by an ultrafiltration membrane for obtaining beta-1,3-glucan oligosaccharide with polymerization degree of 4-15. Performing acidolysis by -b-glucanase and performing enzymolysis comprise dissolving thermal gel (1-2 kg) in 0.1 M of trifluoroacetic acid solution (8 L); hydrolyzing the thermal gel for 8-24 hours at 60 degrees C, and regulating pH value to 6 using ammonia water, a mass ratio of thermal gel to enzyme being 10-20:1-2; adding into -b-glucanase, and hydrolyzing for 5-24 hours at 37 degrees C. Performing acidolysis comprises dissolving thermal gel (12 kg) in 0.01 M of barium hydroxide solution (8 L), stirring for completely dissolving the thermal gel, regulating pH value to 7 using sulfuric acid, a mass ratio of thermal gel to enzyme being 10-20:1-2, adding into -b-glucanase, mixing uniformly, regulating pH value of the solution to 6 using anhydrous acetic acid, hydrolyzing for 2-24 hours at 37 degrees C, regulating pH value of the solution to 2-5 using 0.1 M of trifluoroacetic acid, and hydrolyzing for 1-16 hours at 60 degrees C; selecting hollow roll-type membrane with molecular weight cutoff of 15000 Da for separating at 0.5 MPa; at a volume ratio of 1:5, performing ultrafiltration for 25 minutes, and pushing the solution to pass through the membrane by an aqueous solution which has pH value of 6 and has an amount of 0.5 folds of the volume of the obtained oligosaccharide solution; continuously subjecting the trapped fluid to enzymolysis or acidolysis; concentrating the permeate by an interception membrane with molecular weight cutoff of 1000 Da at 0.5 MPa for 25 minutes; and drying the trapped concentrated solution for obtaining -b-1,3-glucan oligosaccharide product.