Spodoptera exigua (Lepidoptera: Noctuidea) is a polyphagous pest that attacks many important agricultural crops. Identifying an insect specimen is a crucial step in entomology. This study demonstrated a molecular method to identify the species of pest and its parasitoid in the case of a lack of a morphological identification key. To facilitate the identification of these pest-parasitoid species, a DNA barcoding approach was used for accurate and time-consuming identification based on nucleotide sequencing analysis of the mitochondrial Cytochrome Oxidase subunit I (COI) gene. DNA barcoding sequences successfully identified both pest and parasitoid species by comparing barcode sequences to the GenBank database. This study provided evidence of Pediobius sp. as a parasitoid of S. exigua in Malaysia.