The mirid bug Apolygus lucorum (Meyer-Dür) is a principal pest of cotton that also causes great damage to many other crops in China. A study was conducted to assess the mortality of A. lucorum from generalist arthropod predators using both molecular methods and a field-cage trial. The species-specific primer pair for the detection of A. lucorum tissues in predators was designed according to the sequences of the cytochrome oxidase subunit I (COI) gene.