Background: Ischemic stroke comprises 85% of all strokes. Atrial fibrillation (AF) is the most common cause of cardioembolism and a leading cause of ischemic stroke.  The diagnosis of paroxysmal AF (PAF) after cerebral ischemia is often difficult to establish because paroxysmal episode may be short and may elude stroke unit monitoring in the acute phase. Objectives: Detection of PAF after ischemic stroke and investigating feasibility and diagnostic accuracy of measurement of the peripheral pulse at the radial artery as a simple non-invasive screening tool for PAF in patients after acute ischemic stroke. Patients and methods: This study was carried on 52 patients with acute ischemic stroke admitted at Neurology Department, Al-Azhar University Hospitals from 1^st November 2014 till the 1^st of June 2015. All patients were submitted to complete medical history, complete physical examination, full neurological examination, routine laboratory investigations, CT scan of the brain, conventional ECG registration and echocardiography. All patients and their relatives were undergoing on training program for peripheral pulse measurement and standardized introduction on the pathophysiology of cardioembolic stroke. Results: Patients with PAF were 11 (21.2 %), patients with AF were 22 (42.3 %), mean age ± SD of patients with AF was 60.273 ± 10.743 years and that of patients with PAF was 59.682 ± 8.283 years. Patients had PAF were 18% males, 82% females, 90.9% had a history of hypertension, 91% had diabetes mellitus, 72.7% had hyperlipidemia, 9% were smokers, 72.7% had IHD (ischemic heart disease) and 81.8% had a history of previous stroke. Patients had AF were 22.7% males, 77.3% females, 90.9% had a history of hypertension, 72.7% had diabetes mellitus, 50% had hyperlipidemia, 13.7% were smokers, 86.4% had IHD  and 90.9% had a history of previous stroke. AF or PAF related ischemic stroke was associated with older age, female gender, hypertension, diabetes mellitus, no smoking and history of previous stroke. Hypertension and diabetes mellitus were significant predictors of newly diagnosed (NDAF) AF or PAF in acute ischemic stroke. Measurements by health care professionals had sensitivity 81.82, specificity 95.12, positive predictive value 81.82, and negative predictive value 95.12 with accuracy 92.31. Measurements by patients themselves had sensitivity 42.86, specificity 53.57, positive predictive value 18.75, and negative predictive value 78.95 with accuracy 51.43. Measurements by the relatives of the patients had sensitivity 55.56, specificity 72.22, positive predictive value 33.33, and negative predictive value 86.67 with accuracy 68.89 Conclusion: Early diagnosis of AF facilitated the detection of patients who should receive oral anticoagulant treatment to decrease risk of stroke. Primary prevention of cardioembolic stroke can be achieved by early discovering AF patients. Patients with diabetes, hypertension, IHD or history of previous stroke are at increased risk of AF or PAF. We suggest that all patients with AF were PAF at first and then converted to established AF. Early detection and management of PAF reduce the occurrence of established AF.