For the setting of control timing, the number of overwintering eggs on host plants and population density of Metcalfa pruinosa nymphs and adults was surveyed in a sesame fields. According to a survey of the overwintering eggs density of M. pruinosa on host plants, they were many in the order of Mugunghwa trees, Oak trees, and Acacia trees. Examined sesame branches within the 50cm was not found population densities of M. pruinosa nymphs and adults, and it was also very low in the sticky trap. The peak density of the adult was highest at 0.13 per trap on 11 after being first investigated on July 3 in a string wrap survey, and then decreased. In a sesame fields, it is judged that the control of the M. pruinosa is due to be 35 days after the end of the insect hatching, and that distribution of host plants is more important in the outside region than inside region.