Objectives: Both elevated blood pressure (BP) and/or depression increase the risk of cardiovascular disease and mortality. This study among treated elderly hypertensive patients explored the incidence of depression, its association (pre-existing and incident) with mortality and predictors of incident depression including any effect of ACE Inhibitor- or diuretic-based antihypertensive treatment. Methods: Data from 6083 hypertensive patients aged ≥65yrs enrolled in the Second Australian National Blood Pressure study were used. Participants were followed for a median of 10.8 years (including 4.1yrs in-trial) and classified into: ‘no depression’, ‘pre-existing’ and ‘incident’ depression groups based on either being diagnosed with depressive disorders and/or treated with an anti-depressant drug at baseline or during the in-trial period. For the current study, end-points were all-cause and any cardiovascular mortality. Results: 313 (5%) participants had pre-existing depression and a further 916 (15%) participants developed depression during the trial period (an incidence of 4% per annum). Increased all-cause mortality was observed among those with either pre-existing or incident depression compared to those without. For cardiovascular mortality, a 24% increased risk was observed among those with incident depression. Incident depression was associated with being female, aged ≥75 years, being an active smoker at study entry, and developing new diabetes during the study period. There was no difference in incident depression between those randomised to either thiazide diuretic-based or ACE inhibitor-based therapy. Conclusion: This elderly cohort had a high incidence of depression irrespective of their randomised antihypertensive regimen. Both pre-existing and incident depression were associated with increased mortality.