BackgroundAdvancements in cancer treatments have successfully improved central nervous system (CNS) cancer survivorship and overall quality of life. As a result, the awareness of the importance of fertility preservation techniques is increasing. Currently, a range of established techniques, such as oocyte cryopreservation and sperm cryopreservation, are available. However, oncologists may be hesitant to refer patients to a reproductive specialist.ObjectiveThe primary aim of the proposed systematic review is to assess the best evidence for fertility preservation techniques used in patients with CNS cancers. It also aims to evaluate outcomes related to their success and complications.MethodsThis protocol was produced in adherence with the PRISMA-P (Preferred Reporting Items for Systematic Review and Meta-Analysis Protocols). Electronic databases will be systematically searched to identify studies that meet our eligibility criteria. Studies will be included if they report at least one type of fertility preserving or sparing technique in male patients of any age and female patients aged <35 years. Animal studies, non-English studies, editorials, and guidelines will be excluded from the review. From the included studies, data will be extracted and synthesized by using a narrative approach and summarized in tables. The primary outcome will be the number of patients successfully undergoing a fertility preservation technique. The secondary outcomes will include the number of retrieved oocytes, the number of oocytes or embryos vitrified for cryopreservation, clinical pregnancy, and live birth. The quality of the included studies will be assessed by using the National Heart, Lung, and Blood Institute risk-of-bias tool for any type of study.ResultsThe systematic review is expected to be completed by the end of 2023, and results will be published in a peer-reviewed journal and on PROSPERO.ConclusionsThe proposed systematic review will summarize the fertility preservation techniques available for patients with CNS cancers. Given the improvement in cancer survivorship, it is becoming increasingly important to educate patients about fertility preservation techniques. There are likely to be several limitations to this systematic review. Current literature is likely to be of low quality due to insufficient numbers, and there may be difficulty in accessing data sets. However, it is our hope that the results from the systematic review provide an evidence base to help inform the referral of patients with CNS cancers for fertility preservation treatments.Trial RegistrationPROSPERO CRD42022352810; https://tinyurl.com/69xd9addInternational Registered Report Identifier (IRRID)PRR1-10.2196/44825