Clopidogrel therapy increases bleeding risk, but whether it influences short-term mortality after peptic ulcer bleeding (PUB) is unknown. The objective was to examine whether clopidogrel use at the time of PUB increases 30-day mortality. We conducted this cohort study in northern Denmark (population 1.7 million). We used the Danish National Patient Registry, covering all hospitals, to identify all patients with a first-ever inpatient diagnosis of endoscopically or surgically confirmed PUB between 1998 and 2008 and their comorbidities. From the prescription database in the region, we ascertained the use of clopidogrel at the time of admission (current use) or before admission (former use) and use of concurrent medications. We obtained mortality data from the Danish Civil Registration System. We used regression modeling to compute mortality rate ratios (MRRs) with 95% confidence intervals (CIs), controlling for potential confounders. We identified 6951 patients with bleeding peptic ulcers. At admission, 122 (1.8%) were current users of clopidogrel, 143 (2.1%) were former users, and 6686 (96.2%) were nonusers. Thirty-day mortality was 5.7% for current users, 7.0% for former users, and 8.0% for nonusers. The adjusted 30-day MRR was reduced in both current and former users, compared with nonusers (MRR = 0.72, 95% CI 0.34, 1.52 and MRR = 0.71, 95% CI 0.38, 1.32, respectively). There was no notable modification of the association within gender or age strata. Although the use of clopidogrel increases the risk of PUB, former use and current use of clopidogrel were not associated with increased short-term mortality after admission for this condition.