The fall armyworm (FAW), Spodoptera frugiperda (Smith), is a major pest native to the Americas. A

recent invasion of FAWs from Africa eastward to South Asia, the Indochina Peninsula, and mainland

China has received much attention due to the considerable economic losses in agriculture. FAWs

can rapidly colonise a new area, likely due to the wide range of host plants, good flying capability,

and high egg production. Therefore, a convenient, quick, and accurate tool for FAW identification

is urgently required to establish a FAW invasion management strategy. In this study, FAW-specific

primers were designed to recognise FAWs on the basis of internal transcribed spacer 1 (ITS1). The

results revealed the accurate FAW recognition of the three congeneric species and eight common

corn lepidopteran pests, especially at their larval stage. Furthermore, species-specific primers have

confirmed their efficacy by using 69 FAW specimens from Taiwan, Thailand, and the United States,

with a 96% success rate, excluding 3 decayed specimens. By using the simple, reliable, and convenient

FAW-specific primers, a pest management programme can be developed not only to reduce

sequencing costs and experimental time from 2 days to 4 h, but eradicate the FAW as soon as it enters

a new area.