Purpose: The impact of brain tumour on subjective cognitive function (SCF) has received little attention despite the implications of these perceptions for quality of life. SCF consists of two related yet distinct components, perceived cognitive impairment (PCI) and perceived cognitive abilities (PCA). This study compared the SCF of adult brain tumour survivors and healthy controls and examined demographic, illness-related, and psychological factors associated with SCF. Method: Sixty-five adult survivors with primary brain tumour (age, 22–75 years), and 65 age- and sex-matched controls were recruited. Participants with brain tumour completed the Brief Test of Adult Cognition by Telephone, Functional Assessment of Cancer Therapy–Cognitive Function (FACT-Cog), ratings of physical symptoms, Depression Scale of the Depression Anxiety Stress Scales-21 (DASS-Depression), and Generalized Anxiety Disorder-7 (GAD-7) scale. Controls completed the FACT-Cog, DASS-Depression, and GAD-7. Results: Adult brain tumour survivors reported significantly greater PCI and lower PCA than controls, after accounting for anxiety. Higher PCI was significantly related to fatigue, pain, treatment-related side-effects, anxiety, and depression. Lower PCA was significantly associated with fatigue, pain, poorer objective cognitive function, lower education, anxiety, and depression. Anxiety uniquely accounted for 9–14% of variance in SCF. Conclusions: Adult brain tumour survivors were found to experience poorer SCF than healthy controls after accounting for anxiety. SCF was related to multiple factors after brain tumour; however, an independent association with anxiety was identified. Implications for Cancer Survivors: These findings highlight the potential value of psychological interventions targeting anxiety and cognitive effects to improve quality of survivorship after brain tumour.