Our (eukaryotic) cells have a complex structure consisting of various organelle; cellular subunits made of lipid membrane. Organelle allows cells to carry various chemical reactions in parallel, to realize complex cellular functions and to construct complex multicellular organisms. However, because of the small size, the organization mechanism of the cellular complex structure remains elusive. In this study, we consider organization of Golgi body; a membrane-bound organelle working as the hub of the cellular logistics. Golgi body has a characteristic morphology; several flattened of lipid membrane sacs
(cisternae) stacking to each other. At the cell division in mammalian cells, Golgi body is newly formed from assembly of small vesicles. We adopted dynamical triangulation method for coarse graining of membrane performed Monte-Carlo simulation to reproduce the Golgi organization process. We found that the control of membrane fusion based on local membrane structure is necessary to organize and maintain the fine Golgi-like shape. We also characterized the self-organization of fine Golgi-like shape via balances among three time scales of vesicle aggregation, membrane shape relaxation and membrane fusion.