Background/Aim. Levodopa, the precursor of dopamine, is a substitute therapy for Parkinson's disease. Long-term application of levodopa causes fluctuation in motor response and the occurrence of involuntary movements or dyskinesia. The aim of this study was to assess the risk factors for dyskinesia in Parkinson’s disease (PD) patients undergoing treatment with levodopa. Methods. We included 177 consecutive outpatients with PD, who had been undergoing treatment for at least six months. A semi-structured interview was used to collect demographic and clinical data as well as a number of clinical scales. Results. Patients with dyskinesia (n = 90) were younger at disease onset and had longer disease duration. They had higher Unified Parkinson's Disease Rating Scale (UPDRS) scores and more frequently had other motor complications, such as wearing-off and freezing of gait, as well as non-motor ones, such as psychosis. They took higher levodopa doses and levodopa equivalent doses and were on levodopa therapy for a longer period of time. Multivariate analysis yielded that independent risk factors for dyskinesia were: disease duration of longer than 10 years [relative risk (RR = 2.90), 95% confidence interval (CI) 1.19–7.10; p = 0.019), dopaminergic treatment duration of longer than 94 months (RR = 3.21, 95% confidence interval (CI) 1.05–9.87; p = 0.041) and levodopa dosage of higher than 537 mg (RR = 3.62, 95%IP 1.57–8.35; p = 0.002). Conclusion. We highlight the importance of known risk factors for dyskinesia and their occurrence in the context of advanced, complicated disease.