Starch granules of mungbean observed by microscope and scanning microscope were oval or round, 8∼13μ wide, and 18∼30㎛ long. X-ray diffraction of the starch granules resulted weak crystallinity at 2θ 16.9°. The blue value of the starch was 0.36, amylose content 22.7%, alkali number 8.52, ferricyanide number 1.06, and water binding capacity of 81.6%. Swelling of the starch was negligible until 50℃, thereafter it increased rapidly. Optical transmittance of 0.3% starch suspension was increased rapidly from 65℃ and the gelatinization at 65∼90℃ was of single stage. Amylogram patterns of the 6.7 and 8% starch solution were similar with no peak viscosity. The time constant for retrogradation of 40% starch gel stored at 21℃ was 1.99 days.