【Objective】To determine the effect of ovarian stimulation or in vitro maturation for fertility preservation in female cancer patients. 【Methods】 A retrospective study was conducted in 27 females who underwent fertility preservation procedures in our center.【Results】Female patients were included in this study with an average age of 27.1. Patients spent on average for 6.8 d to retrieve oocytes since their attendance day. Total amount of Gn was on average 910 U per patient and for patients with breast cancer，the average estrogen level on trigger day reached 360 pg/mL. The maturation rate of oocytes from ovarian stimulation cycles was 82.6% ，which of that in emergency in- vitro maturation cycles was 38.1%.【Conclusion】The development capability of oocytes from cancer patients are comparable with those of other infertility patients. Peak estradiol levels were controlled by the administration of letrozole. In vitro maturation of oocytes performed at random time of the menstrual cycle may result in a lower maturation rate ，which is associated with the time limit of the follow- up cancer treatment. In conclusion，clinicians should consider a more holistic approach for female cancer patients，which focuses not only on the characteristic of the primary cancer but also on the phase of the menstrual cycle at their attendance day.