Background: To determine the difference in the radiation exposure of patients undergoing conventional single-energy computed tomography pulmonary angiography (SECTPA) and dual-energy CT pulmonary angiography (DECTPA) and determination of the benefits of both methods in the diagnosis of pulmonary embolism (PE). Material and Methods: In this single-center retrospective study, 105 consecutive CTPA examinations performed on dual-source dual-energy CT scanner November 2018–December 2020 at St. Michael’s University Hospital Radiodiagnostic Clinic, Bratislava, Slovakia were reviewed for detection of acute PE and dose-length product (DLP) in each examination was noted and compared in SECTPA and DECTPA. The 105 examinations included 95 patients (mean [M] = 60.5 years, range 20–88 years). Results: Of the 95 examined patients, 92 had an initial examination, of whom 22 had confirmed acute PE (23.9% of initially examined patients, 11 by SECTPA, and 11 by DECTPA), in 70 patients (i.e., 76.1%) PE was not present. The DLP in DECTPA was M = 344.4 mGy × cm, and in SECTPA M = 176.7 mGy × cm. Conclusions: Mean DLP in DECTPA was almost 2-times higher than in SECTPA (with a statistically significant difference, p < 0.001), while in three-quarters of patients, acute PE was not confirmed, which is in the era of CTPA overuse unnecessary radiation exposure. However, DECTPA with iodine perfusion maps is superb in the follow-up of patients with confirmed PE by detecting small chronic subsegmental PE and thus preventing chronic complications in the form of chronic thromboembolic pulmonary hypertension, which, if untreated, is fatal. Med Pr Work Health Saf. 2025;76(1)