Objectives - To study the prevalence of post-concussion symptoms (PCS) 5-7 years after mild head injury (MHI) and to investigate whether patients suffer from more symptoms than the normal population. Methods - We conducted a 5- to 7-year follow-up of patients (n = 89) with MHI. Post-concussion symptoms were quantified with the Rivermead Post Concussion Symptoms Questionnaire (RPQ) and health-related quality of life (HRQL) was measured with the EuroQol-5D (EQ-5D). We also quantified subjective general health state with the EuroQol Visual Analogue Scale (EQ-VAS). An age- and sex-matched, but otherwise randomly chosen control group of 89 persons was recruited from the National Population Registry for a cross-sectional comparison. Twenty-eight patients (30%) and 27 (30%) controls responded. Results - Patients reported significantly (P = 0.017) more PCS (median RPQ score 10, 95% CI 2-20) than controls (median 2, 95% CI 0-4). They also reported significantly (P = 0.008) lower HRQL (median EQ-5D score 0.866, 95% CI 0.796-1.000) than controls (1.000, 95% CI 1.000-1.000), but there was no difference between the groups in their subjective ratings of general health state. Conclusions - Patients reported significantly more PCS and lower HRQL 5 to 7 years after MHI than age- and sex-matched controls from the normal population.