Embryonic stem cells(ESC) are undifferentiated totipotent cells that could be differentiated in vivo into any kind of cells theoretically,including germ cells.The germ cells undergoing meiosis that could influence the genetics of progeny ultimately,so successes of the differentiation from ES into germ cells in vitro means great leap not only of significance in development technically but also be a challenge to science interfering with traditional ethic conception.The present work is going to summarize the current research literatures on this topic.