The effect of dynamic high-pressure micro-fluidization (DHPM) at 80, 120, 160, and 200 MPa on the structure of maize amylose was investigated using scanning electron microscopy (SEM), atomic force microscope (AFM), Xray diffraction, and FT-IR spectroscopy. SEM analysis showed that the surface appearances of maize amylose were altered and the starch granules were partially congregated together after DHPM treatment. AFM images showed that the treated starch molecules are cross-linked to each other and arranged in a close mesh structure. Xray diffraction spectra and IR spectra indicated that relative crystallinity declined gradually with the pressure increasing. The results provide a theoretical basis for starch modification of DHPM.