Background: Diagnosis of pulmonary embolism (PE) is challenging as the symptoms of PE are non-specific. Computed tomographic pulmonary angiography (CTPA) has emerged in recent years as the imaging modality of choice. However, the wide availability of Computed tomography (CT) has led to concerns about the overutilization of CTPA. Use of D dimers and clinical probability scoring tools like the revised Geneva scores are invaluable in stratifying patients according to the probability of PE. Therefore, the study aimed to calculate the diagnostic yield, clinical probability scores and overutilization of CTPA in patients with suspected PE. Objective: To determine the diagnostic yield, clinical probability score, utility and overutilization of CTPA in patients with suspected pulmonary embolism at Moi Teaching and Referral Hospital (MTRH). Methods: This was a cross-sectional study conducted at the MTRH between September 2022 and August 2023. A consecutive sampling technique was applied and recruited 102 adult patients. Demographics, revised Geneva scores and D dimers results were recorded. Patients were subsequently categorized into low, intermediate and high probability for PE. Results: The diagnostic yield was 29.4%. On the Revised Geneva score, 7 (6.9%) were low risk, 84 (82.4%) moderate risk and 11 (10.8%) high risk. 0%, 25% and 81% in the low, intermediate and high risk groups were diagnosed with PE respectively. 50(49.0%) of participants had positive conventional D dimers while 52(51.0%) were negative. The revised Geneva score had a sensitivity, specificity, positive predictive value and negative predictive value of 83.3%, 44.4%, 38.5% and 86.5% respectively. 7 patients (6.9%) had negative D dimers, low risk on the revised Geneva score and no PE on CTPA. Conclusion: The use of D dimers combined with the revised Geneva clinical probability score will stratify patients into risks groups for PE and help to reduce overutilization of CTPA.