The pattern of seed storage protein, vicilin, deposition and site of intracellular localization was examined in cotyledon cells of pea (Pisum sativum) seed using the immunocytochemical methods. The vicilin was confined to the cisternae fo the rough endoplasmic reticulum and dictyosome as well as protein granules newly formed in rough endoplasmic reticulum. Vacuolar protein deposites and protein bodies were also labelled by gold particles. After small protein bodies were formed in the rough endoplasmic reticulum, they were transported to large protein bodies and then fused together. Electron dense protein granule, elaborated in the dictyosome, appears to be transported from dictyosome to protein body. A few unlabelled protein granules seem to be accumulated in other type of proteins than vicilin.