To analyze the therapeutic effect of unilateral adnexectomy for treating patients with early ovarian cancer, and to study its influence on the menstruation and fertility function of these patients. Methods: The clinical data of 101 patients with early ovarian cancer from December 2016 to December 2020 were collected. According to different treatment, these patients were divided into group A (45 patients with unilateral adnexectomy) and group B (31 patients with unilateral/bilateral ovarian mass removal), and group C (25 patients with unilateral/bilateral ovarian mass removal combined with staging surgery). The perioperative indicators, the status of anxiety and depression, and the postoperative menstruation and pregnancy situation within 1 year of the patients were compared among the three groups. Results: The operative time and the intraoperative blood loss of the patients in group A were significantly lower than those of the patients in the other two groups (P＜0.05). There were 6 patients with the recurrence of ovarian cancer in group B, and then they lost their fertility completely after tumor cell reduction therapy. Within 1 year after surgery, the proportion of normal menstruation of the patients in group A (84.4%) and in group B (80.5%) was significantly higher than that (56.0%) of the patients in group C. The success rate of pregnancy of the patients in group A (73.3%), in group C (36.0%), and in group B (6.5%) had decreased gradually (all P＜0.05). All the babies in the three groups developed normally and no any baby with malformations was observed. The scores of SAS and SDS of the patients in the three groups after surgery had decreased significantly, and which of the patients in group A were significantly lower than those of the patients in the other two groups (P＜0.05). Conclusion: Unilateral adnexectomy for treating the patients with early ovarian cancer has outstanding effective, which can improve their menstrual and psychological condition, and can effectively preserve their reproductive function.