Development of immature ovarian follicles in vitro is a feasible strategy for preservation of biologically valuable genetic sources and infertility treatments. Especially, ovarian tissue banking is an effective method for protecting against infertility caused by strong cancer therapy. Grafting, however, carries a risk of malignant cell recurrence. It is necessary to develop culture methods for immature follicles from young women who have recovered from cancer, but such systems are not currently well developed. It is difficult to induce normal growth in vitro in early stage follicles. In this article, the current status of ovarian immature follicle growth culture as well as multi-step culture methods is reviewed.