Tectal plate gliomas (TPGs) are a heterogeneous group of uncommon brain tumors. TPGs are considered indolent and are usually managed conservatively but they have the potential to transform into higher-grade tumors. The aims of this study were to investigate the natural history of adult TPG, treatment outcomes, and overall survival.A retrospective cohort analysis was performed of adult patients with TPG between 1993 and 2021. Baseline clinical, radiologic, and management characteristics were collected. The primary outcome was tumor progression, defined as increasing size on radiologic assessment or new gadolinium contrast enhancement. Secondary outcomes included management and mortality.Thirty-nine patients were included, of whom 23 (52.2%) were men. Median age at diagnosis was 35 years (interquartile range, 27-53). Radiologic tumor progression was observed in 8 patients (20.5%). The 10-year progression-free survival was 72.6% (95% confidence interval [CI], 0.58-0.91). The 10-year overall survival was 86.5% (95% confidence interval, 0.75-1.0). Cerebrospinal fluid diversion procedures were used in 62% of the cohort (n = 24). Seventeen patients (43.6%) underwent at least 1 endoscopic third ventriculostomy, whereas only 6 patients (15.4%) underwent at least 1 ventriculoperitoneal shunt.TPG has an overall favorable clinical prognosis, although progression occurs in 1 in 5 patients. Showing accurate factors by which patients with TPG may be risk stratified should be a key area of further research. A follow-up duration of 10 years would be a reasonable window based on the radiologic progression rates in this study; however, larger cohort studies are needed to answer both questions definitively.