The physicochemical properties of the endosperm components of sugary-2 mutant rice were examined, characterized and compared to that of the normal type. The protein and amylose contents as well as the palatability score were all higher in sugary-2. For fatty acids, palmitic, linoleic and linolenic acid were all present in significantly higher proportion in the sugary-2 mutant. Analysis of the minor sugars in the endosperm showed that inducing the sugary-2 gene did not increase the amount of all sugar types, higher amounts were only measured in rhamnose and fucose content. Regarding the characteristics of starch granules, the ratio of longer glucose chain length to the distribution of endosperm starches decreased with the insertion of the sugary-2 mutant gene. And it was also found that the gelatinization properties of sugary-2 mutant rice showed a general trend of lower gelatinization temperature while the gelatinization enthalphy was considerably lower.