The objective of the study was to compare the mortality in HIV infected individuals to the general population, and to explore the relative contribution of HIV to mortality before and after the introduction of highly active antiretroviral therapy (HAART). All HIV patients attending Ullevål University Hospital, Oslo, Norway before (cohort 1) and after (cohort 2) the introduction of HAART were included. Causes of deaths were classified as HIV related or not. Mortality in the Norwegian general population was standardized according to the distribution of age and gender in our cohorts. Ratios between mortality in our cohorts and the standardized mortality were calculated. The risk ratio (RR) for 5-y mortality compared to the general population was 22.6 (95% confidence interval (CI), 19.5-26.4) in cohort 1 (n = 782), and 3.96 (95% CI 2.25-6.97) in cohort 2 (n = 398). The non-HIV related mortality RR was 4.42 (95% CI 3.18-6.13) in cohort1 and 0.89 (95% CI 0.29-2.76) in cohort 2. Higher age and low CD4 cell count were associated with increased mortality. Thus, in the HAART era the mortality in HIV patients was reduced by 80%. However, the mortality in the HAART era was still 4 times higher than in the general population.