OBJECTIVE: Because of its high prognostic value, neuropsychological assessment plays a crucial role in the neuro-oncology setting. Subjective and objective cognitive performance correlate only to a limited extent, and subjective cognitive performance is strongly dependent on emotional state. We postulate that the relation of subjective and objective cognitive performance depends on tumor laterality. METHODS: In this prospective study, N = 63 patients with brain tumors underwent a neuropsychological test battery, including assessment of subjective cognitive function (attention, memory, executive), and symptoms of depression and anxiety before surgery. Patients with psychiatric comorbidity or severe neurological conditions were excluded. RESULTS: There were no significant differences in subjective and objective cognitive function, symptoms of depression and anxiety between left (N = 37) and right (N = 26) hemisphere tumors. All measures of subjective cognitive function correlated highly significantly with symptoms of depression and anxiety in left hemisphere tumor patients (all r ≥ 0.470). In right hemisphere tumor patients, there was no relation between subjective cognitive function and emotional state. Significant laterality differences for correlations of subjective and objective cognitive function were not found and were not significant within the two groups. CONCLUSIONS: Even when unbiased by symptoms of anxiety and depression, right hemisphere tumor patients show the same discrepancy in subjective and objective cognitive function as left hemisphere tumor patients. This discrepancy may be based on a different mechanism in right hemisphere tumor patients.