Apicomplexan protozoa contains a highly reduced plastid-like organelle termed apicoplast. The research on evolutionary origin of apicoplast is a topic of long-term intense debate, by far, hasn't still reached congruent conclusion though a variety of molecular technologies were employed, so that it become a typical case in plastid origin field. In this paper , we reviewed the molecular evidence for apicoplast evolutionary origin, predicting the potential source of novel molecular evidence as clues for further studying.