Worldwide, increasing numbers insecticide resistant insect is one of the main problem in this agricultural era. To manage the insecticide resistance, IRAC suggest some tips for farmers : 1. Sequence or alteration of insecticide based on MOA 2. Choosing the effective insecticide. In this point raised following question : How to distinguish the effective or non-effective insecticide. Until now, bioassay is the right answer. However that is a very time-consuming, labor-intensive, and costly process, so we were hoping that molecular based diagnosis could be alternate. It can summarized following steps : 1. Identification of insecticide resistance mechanism 2. Marker development 3. Molecular diagnosis 4. Selection of non-effective insecticide. Here we focused on the development of insecticide resistance marker. Point mutation in target site of insecticide is a good example. Up or down-regulation of specific gene and/or existence of chimeric gene is another example from Helicoverpa armigera.