Background: Patient health-related quality of life (HRQL) is an important health outcome with lower HRQL associated with adverse events in patients with ischaemic heart disease (IHD). Design: Baseline health-related quality of life was investigated as a predictor of 5-year all-cause mortality and cardiac readmissions in Danish patients with IHD. Methods: The international HeartQoL Project survey was designed to develop a core HRQL questionnaire for patients with IHD. Baseline scores on each of the 14 items ultimately included in the HeartQoL questionnaire were linked to Danish national health registries and hazard ratios for mortality and readmissions were estimated using Cox regression models. Results: Among 938 eligible Danish patients with IHD, 662 (70.6%) participated in the international HeartQoL Project. During the 5-year follow-up, 83 patients died and 196 patients were readmitted. Adjusted analyses showed a significant linear association between all-cause mortality and both lower global HRQL (HR= 1.67, 95% CI: 1.26-2.23; p <0.001) and physical scores (HR= 1.71, 1.33-2.21; p < 0.001) and between read mission and both lower global (HR= 1.73, 1.41- 2.12; p <0.001) and physical scores (HR= 1.63, 1.35-1.96; p <0.001). A significant, but non-linear, effect was found for emotional HRQL score on outcomes. Conclusion: This study shows a significant and linear relationship between lower global and physical HRQL scores in patients with IHD and 5-year all-cause mortality and cardiac readmission.