1. A founding female of Polistes chinensis antennalis Perez makes as many as 30 to 40 cells in the period previous to the emergence of her youngs, the workers. 2. The method of enlarging her nest is assumed to be highly correlated with the nesting-site. 3. The founding female stops oviposition for some days after the hatching of her 'first larva, but the duration of her non-oviposition period varies and has close connection with the nesting-site. 4. Only fluids are fed to la r vae younger than the third instar, and both fluids and flesh are given to larvae older than the fourth instar. 5. Fluids given to larvae may be divided into two kinds, i. e. the nectar or honey dew excreted by aphides and the body fluids of her prey. 6. The number of workers successfully developed from larvae under the care of the founding female alone is 5 to 10. 7. As the workers begin to emerge one after another, the founding female leaves the nest no more and concentrates her task both to care for her brood and oviposition. 8. At the moment of the emergence of new workers the nest development enters into a new or the second phase. 9. If the founding female dies , the number of ovipositing workers increases. 10. If the male sex begins to appear in the nest, the nest development stops. In one rare case the males developed from eggs laid by the founding female emerged as early as at the middle of June, and in this case the colony of the nest has been dissolved.