Background/Aim. Benign paroxysmal positional vertigo is one of the most frequent peripheral vestibular system disorders. The aim of this study was to examine the efficacy of the Epley maneuver in treating benign paroxysmal positional vertigo of the posterior semicircular canal (p- BPPV) and to discover possible causes of failure. Methods. This prospective study included 75 patients. In all the cases medical history showed and the positioning Dix-Hallpike test confirmed the diagnosis of p-BPPV. We also performed clinical ENT examination, searching for spontaneous nystagmus, vestibulospinal tests, caloric test, and audiometry. All the patients were treated by the modified Epley canalith repositioning maneuver. The patients were followed up at the intervals of seven and, fourteen days, and one, tree, and six months and one year. The maneuver was repeated if vertigo and nystagmus on control positioning test persisted. The transition from positive into negative Dix Hallpike test after one or two Epley maneuver was considered as success in treatment. Results. After the initial Epley maneuver the recovery rate was 90.7%, and after the second 96%. In three (4%) patients with secondary p-BPPV, symptoms did not cease even after the second repositioning maneuver. The etiology of p-BPPV had a significant effect on the maneuver’s success rate (p < 0.01), whereas duration of symptoms, age and gender had no effect (p > 0.05). After a successful treatment 11 (14.66%) patients had recurrent attack of BPPV during the first year. Conclusion. The Epley maneuver is very successful repositioning procedure in treating p- BPPV. The patients with idiopathic form p-BPPV showed higher success rate with Epley maneuver than those with secondary p-BPPV.