The structure of starch can be divided into four levels: molecule, blocklet, shell and granule. Based on the starch gelatinization characteristics determination program of six kind of starches (sweet potato, cassava, pea, mung bean, corn and wheat), outer shells from different starches were obtained by using insufficient gelatinization method (treatment temperature from 95℃ to 73~89℃, pH value from 7 to 1.5 in acetic acid solution of 7.1mol/L). The results of scanning electron microscopy (SEM) and laser scanning confocal microscopy (LSCM) showed that the outer shells were hollow, distorted, rough and had openings or holes, compared with the native starch granules. Acetic acid can affect the morphology of starch, during the gelatinization process almost all the internal substances of starch granules were dissolved into the solution, and the molecular distribution of outer shells became loose or partially dissolved with the expansion of particles. Starch outer shells can maintain its own structure better in the treatment process, which was quite different from the internal structure. The thickness of outer shells was ranged from 50nm to 470nm, the amylose content and relative crystallinity were lower than those of the native starch, and the molecular weight ranges was 4.3×107~5.2×107g/mol, which was close to the molecular weight of native starch (3.8×107~4.7×107g/mol). There were no significant correlations between the thickness of outer shells and the particle size, amylose content and relative crystallinity of starch. The outer shell of corn starch was relatively complete, which can be used as a type of biomacromolecule slow-release self-assembly coating material and had a broad application prospect.