OBJECTIVE: Glioblastoma multiforme (GBM) following traumatic brain injury (TBI) is very rare and has not been comprehensively characterized by current literature. This systematic review aimed to characterize demographics of patients with post-TBI GBM. METHODS: A systematic review of case studies and case series was conducted for reports published up to April 2023. All case reports that satisfied the criteria for diagnosing post-TBI GBM were included. The JBI case report appraisal was used to assess the quality of reporting of included articles. RESULTS: Our review comprised 13 studies including 16 patients, most of whom were male (81%). Contusive TBI was the most frequent initial insult observed, with most patients requiring surgical intervention to manage TBI. The median latency between TBI and GBM diagnosis was 9.5 years with a negative correlation observed against patient age at TBI occurrence, but a positive correlation was noted for patients with IDH-wildtype GBM. Median age at GBM diagnosis was 56 years. CONCLUSIONS: This systematic review highlights a possible link to GBM development at the previous TBI site. Updated criteria for identifying post-TBI brain tumors are proposed to keep abreast with the latest advances in classifying central nervous system tumors. To establish a definitive link, a large-scale international multicenter study investigating the occurrence of World Health Organization grade IV IDH-wildtype de novo GBM after TBI is crucial. Regular monitoring, especially in middle-aged and older patients with TBI, is advisable.