Abstract: Aryloxyphenoxypropionate (APP) herbicides can effectively inhibit plastid acetyl-coenzyme A carboxylase (ACCase) of gramineous plant, and have been widely used to control gramineous weeds in the field. Gramineous weeds resistant to APP herbicides have become widespread after the long-term use of ACCase inhibitors, which are mostly caused by amino acid mutation in chloroplast ACCase carboxyltransferase (CT) domain. Among all of the amino acid mutations, Ile1781/Leu mutation is the most interesting one, which is found in almost all the resistant weeds. A Leu at the specific location may lead to APPs herbicides resistance in some gramineous weeds. The research progress of ACCase CT domain and molecular mechanism of resistance to APPs herbicides were summarized in this paper in order to provide useful information and references for further study of APPs herbicides resistance. Potential problems in the study of molecular mechanism of weeds resistance to APPs herbicides were also discussed.