Aims Low-density lipoprotein cholesterol predicts cardiovascular events in patients with diabetes. However, it is uncertain whether serum triglycerides level is also associated with an occurrence of future cardiovascular events in diabetic patients. We aimed to test whether serum triglycerides is associated with first cardiovascular events in diabetic patients. Methods and results We recruited 5042 participants with diabetes mellitus from the standard versus intEnsive statin therapy for hypercholesteroleMic Patients with diAbetic retinopaTHY (EMPATHY), multicenter, prospective, randomized, open-label, blinded-endpoint study. Median follow-up was three years. We evaluated an association of serum triglycerides with first cardiovascular events in cox-regression hazard models adjusted by age, sex, hypertension, current smoking, low-density lipoprotein cholesterol, and body mass index. Cardiovascular events were defined as (a) major adverse cardiac events including myocardial infarction, stroke, or cardiac death; and (b) cardiovascular diseases including myocardial infarction, unstable angina, ischemic stroke, or large artery disease or peripheral arterial disease. Serum triglycerides were associated with major adverse cardiac events (adjusted hazard ratio: 1.021 per 10 mg/dl; 95% confidence interval: 1.007–1.035; p = 0.0025) and cardiovascular diseases (adjusted hazard ratio: 1.023 per 10 mg/dl; 95% confidence interval: 1.013–1.034; p = 0.0000077). Comparing the top quintile (>185 mg/dl) with the bottom quintile (<79 mg/dl), the adjusted hazard ratio increased 1.89 (95% confidence interval: 1.03–2.80, p = 0.04) for major adverse cardiac events, and 1.90 (95% confidence interval: 1.18–3.07, p = 0.007) for cardiovascular diseases. There were no overall interactions of triglycerides and treatment assignment (standard/intensive statins) on both outcomes ( p-trend = 0.33 for major adverse cardiac events, p-trend = 0.62 for cardiovascular diseases). Conclusions Serum triglycerides were associated with first cardiovascular events among high-risk diabetes patients with hypercholesterolemia and retinopathy.