This study was aimed to manufacture maltooligosaccharides(MO) and isomaltooligosaccharides(IMO) using rice flour. To determine the optimal condition of enzyme reaction(liquefaction, saccharification and transglucosylation), Termamyl 2X, Maltogenase L, Promozyme D2, Fungamyl 800L and Transglucosidase L were used. The contents of MO and IMO were examined by HPLC with charged aerosol detector(HPLC-CAD) in each manufacturing process. Liquefaction reaction of rice flour was performed according to different Termamyl 2X concentration(0.025%, 0.05%, 0.075%, 0.1%) and reaction time(1h, 2hs). As a result, reaction with 0.075% of Termamyl 2X during 2hrs was the optimal condition. For the preparation of maltooligosaccharides, different saccharification enzymes were added and total maltooligosaccharide contents were compared. As a result, the highest total maltooligosaccharide content was 108.31 g/L when saccharification enzyme was not added. Therefore, it was concluded that the maltooligosaccharide preparation was possible only by the liquefaction reaction. In order to optimize the production of isomaltooligosaccharides, the selection of enzyme, optimal enzyme concentration, and optimal enzyme reaction time were investigated. As a result of the enzyme selection experiment, Maltogenase L, Promozyme D2, and Transglucosidase L, which produced the most total isomaltooligosaccharide at the same time, were selected as the optimum enzyme combination. Optimal enzyme concentration was 0.0015% Maltogenase L, 0.05-0.1% Promozyme D2 and 0.1% Tansglucosidase L. This condition decreased glucose contents and increased the content of isomaltooligosaccharide with high degree of polymerization. Change of sugar contents was observed every 6 hours to determine optimal enzyme reaction time. As a result, reaction for 36 hrs was determined as optimal conditions. The isomaltooligosaccharides prepared under optimal conditions showed isomaltose, 35.11 g/L; panose, 11.97 g/L; isomaltotriose, 19.95 g/L; isomaltotetraose, 7.46 g/L; isomaltopentaose, 1.05 g/L at 18 brix and the ratio of isomaltooligosaccharide in the total sugar was 56.37%. To confirm prebiotc effect on isomalto- oligosaccharides, growth of intestinal microflora (Lactobacillus acidophilus KCTC 3140, Lactobacillus delbrueckii subsp. lactis KCTC 3636, Lactobacillus delbrueckii subsp. bulgaricus KCTC 3635, Lactobacillus reuteri KCTC 3594, Lactobacillus gasseri KCTC 3181, Lactobacillus rhamnosus KCTC 5033, Escherichia coli KCTC 1682 and Salmonella spp.) was evaluated. The growth of Lactobacilli was enhanced, but the growth of Escherichia coli and Salmonella spp. was inhibited.