Insect specific ascoviruses have a circular DNA genome in the range of 119 -186 kbp. They are only recently discovered due to no discernable symptom of insects infected with ascovirus. Since ascoviruses are transmitted by parasitic wasps in the field, extensive applications of broad spectrum chemical insecticides reduce the populations of wasps thus lead to scarcity of ascovirus in the environment. Ascoviruses were firstly discovered in noctuid larvae in the South East and West coast of the US in the late 80s. However, in the 70s, ascovirus - like particles were also reported in fire - ants ( Hymenoptera) and alfalfa weevil (Coleoptera). Furthermore, ascovirus was discovered in the larvae of Diadromus pul-chellus of Hymenoptera in southern France of Europe. These data suggest that ascoviruses might exist in different orders of insects such as Lepidoptera, Hymenoptera and Coleoptera, and have a global distribution. This is supported by the fact that ascoviruses have been reported in Australia, Indonesia, France, and USA. Interestingly, no ascovirus has been reported in large countries such as China, India or all of Africa. Efforts are needed to isolate more ascovirus in countries such as China and India and within the continent of Africa to confirm its world distribution, coevolution with insects, and the ecological significance in agriculture and natural environments.