OBJECTIVE: Although associated with adverse outcomes in other cardiopulmonary conditions, the prognostic value of elevated glucose in patients with acute pulmonary embolism (PE) is unknown. We sought to examine the association between glucose levels and mortality and hospital readmission rates for patients with PE. RESEARCH DESIGN AND METHODS: We evaluated 13,621 patient discharges with a primary diagnosis of PE from 185 acute care hospitals in Pennsylvania (from January 2000 to November 2002). Admission glucose levels were analyzed as a categorical variable (≤110, >110-140, >140-170, >170-240, and >240 mg/dL). The outcomes were 30-day all-cause mortality and hospital readmission. We used random-intercept logistic regression to assess the independent association between admission glucose levels and mortality and hospital readmission, adjusting for patient (age, sex, race, insurance, comorbid conditions, severity of illness, laboratory parameters, and thrombolysis) and hospital (region, size, and teaching status) factors. RESULTS: Elevated glucose (>110 mg/dL) was present in 8,666 (63.6%) patients. Patients with a glucose level ≤110, >110-140, >140-170, >170-240, and >240 mg/dL had a 30-day mortality of 5.6, 8.4, 12.0, 15.6, and 18.3%, respectively (P < 0.001). Compared with patients with a glucose level ≤110 mg/dL, the adjusted odds of dying were greater for patients with a glucose level >110-140 (odds ratio 1.19 [95% CI 1.00-1.42]), >140-170 (1.44 [1.17-1.77]), >170-240 (1.54 [1.26-1.90]), and >240 mg/dL (1.60 [1.26-2.03]), with no difference in the odds of hospital readmission. CONCLUSIONS: In patients with acute PE, elevated admission glucose is common and independently associated with short-term mortality.