Abstract: Three barley subvarieties Hua7618 (non-waxy), 20A2 (waxy) and Hua2012 (osculant subvariety), which were different in endosperm types, were used in this report. During endosperm development, the initiation and accumulation of starch and storage protein as well as their morphological changes in endosperm cells of those subvarieties were observed sequentially by optical microscope and transmission electron microscope. The results showed that in Hua7618 endosperm cells, the size increase of large starch granules was the quickest and the average volume of them till grain maturation was the largest compared with the other subvarieties, while the 1 000-grain weight and the number of small starch granules were the greatest and the content of protein was the least. The situation in 20A2 endosperm cells was just opposite to Hua7618, and the situation in Hua2012 was intervenient. One amyloplast contained one large starch granule in endosperm cells, its number hardly increased after 13 days after flowering. Protein bodies were dispersed spherical particles at the prophase of caryopsis development. They fused with each other at the anaphase of caryopsis development and deposited among starch granules. Nuclei in endosperm cells deformed gradually at the metaphase of caryopsis development, and the initiation of small starch granules occurred during or after nuclei disruption.