Apicomplexa is a protozoan class of obligate intracellular parasites,including many important human and veterinary pathogens such as Toxoplasma gondii,Cryptosporidium spp.,Plasmodium spp.,Babesia spp.,Eimeria spp.and so on.The infection and disease of Apicomplexa is an important research area,however,the molecular mechanisms underlying transcriptional regulation in apicomplexan parasites remain obscure.Previous studies suggested that the apicomplexan AP2(ApiAP2)family of DNA binding proteins may be a major class of transcriptional regulators in Apicomplexan.In this article,the latest progress for the function of AP2 proteins was reviewed.