Objective: To compare the safety between cervical conization (CC) alone and hysterectomy for patients with adenocarcinoma in situ (AIS) of the cervix. Methods: Patients diagnosed with AIS after CC during 2007–2021 were identified by computerized databases at Women’s Hospital of Zhejiang University School of Medicine. A total of 453 AIS patients were divided into 2 groups according to uterus preservation: hysterectomy group (n=300) and CC(s) alone group (n=153). The prevalence of residual disease and disease recurrence was compared between patients treated by CC(s) alone and hysterectomy. The prevalence of residual disease in specimens from women who had a hysterectomy and repeat CC were compared between positive and negative margins of CC. The factors influencing residual disease and disease recurrence were assessed. Results: Among 310 specimens from women who had a hysterectomy or repeat CC, the prevalence of residual disease was 50.6% (45/89) for a positive margin and 2.3% (5/221) for a negative margin (p=0.000). Four patients had recurrence of vaginal intraepithelial neoplasia in those treated by hysterectomy and one had recurrence of cervical squamous intraepithelial neoplasia in those treated by CC(s) alone. The prevalence of recurrence was 0.7% (1/153) for CC(s) alone and 1.3% (4/300) for hysterectomy (p=0.431). Hysterectomy did not influence residual disease or disease recurrence. Conclusion CC is an efficacious and safe option for patients with AIS of the cervix provided the margin is negative.