This paper deals with the life history of Scolitantides orion Pallas, based on the field and laboratory observations conducted during the spring, 1972 to the fall, 1973 in Kwangnung, Kyongki-Do, central Korea. 1. This species is distributed in north and central Korea. It is very rare in Kwangnung. 2. The food plant is Sedum sarmentosum Bunge. 3. Egg: The shape is flat, "turban-shaped", 0.70mm in diameter, 0.30-0.33mm in height. The color is grayish white. Its surface is ornamented with irregular net-like sunken pits, Egg Period is about 13 days. 4. Larva: It lasts from the beginning to the middle of May. The larval stage consists of four instars. Each instar larval period is as follows: 1st instar 8 days; 2nd instar, 6-9 days; 3rd instar, 7-8 days; 4 th instar, 11-13 days. 3. Pupa: Body length is 8.5-9.0mm. The color is brown with irregular dark spots on its body. The larva pupates under pebbles near the food plant and the pupa stays over the winter. 6. Adult: It emerges once a year. Newly emerged adults occur from the end of April to the beginning of June. It lays a single egg on the upper-surface or under-surface of a leaf of the food plant.