In order to reduce the oil absorption of mung bean starch (MBS) on the basis of maintaining its crispy characteristics， this paper used mung bean starch (MBS) as raw material to investigate the effects of freeze-thawed (FT) and ultrasonically-assisted freeze-thawed (U-FT) treatments on the effects of freeze-thawed (FT) and ultrasonic-assisted freeze-thawed (U-FT) treatments on the oil-absorption characteristics and structural properties of mung bean starch. The influence of ultrasound-assisted freeze-thawed treatment on the changes of oil absorption and structural properties of MBS was evaluated by analyzing the oil absorption rate， adsorption properties， particle size distribution， contact angle， functional groups， crystalline properties， thermal properties and microstructure. The results showed that both FT-MBS and U-FT-MBS decreased the oil absorption of starch， in which ultrasonic power of 180 W and two freeze-thaw cycles resulted in a significant decrease in the oil absorption of MBS (P<0.05) and a remarkable increase in the water absorption of starch (P<0.05). And the total oil adsorption rate of MBS obtained from both treatments reduced by 5.51% and 10.25% respectively in starch-oil simulated frying system compared to the original starch. The results of structural characterization revealed that FT-MBS had a rough surface and a denser structure； U-FT-MBS particles had larger and irregular shapes， and the changes in the moiety and rough surface altered the starch's oleophobicity. The two treatments resulted in a decrease in the specific surface area of the MBS particles and an enlarged average particle size， which resulted in an increase in the oleophobicity of the starch granules and a decrease in the degree of crystallinity by 3.61% and 6.54%， respectively. Taken together， the modified treatments reduced the oil absorption of MBS before and after frying. A significant reduction in oil absorption was observed for U-FT-MBS， which was attributed to the fact that this treatment enhanced the interaction between MBS and water molecules， altered the short-range ordered structure of starch， delayed the pasting process， and reduced the decomposition of the starch structure during deep-frying， which in turn inhibited the penetration of oil.