Background/aim: This study aims at examining the effects of Pilates training on the transversus abdominis (TrA) and internal obliques (IO) muscle thickness and core endurance in different positions in patients with Parkinson’s Disease. Materials and methods: Patients were divided into 2 groups as Pilates training (n = 13) and control (n = 10) groups. Pilates training was performed twice a week for 6 weeks. The participants’ muscle thickness and core endurance were measured at the beginning of the study (pretraining), and the effectiveness of Pilates training was then assessed in the 6th week (posttraining) and in the 12th-week follow-up. The thickness of the TrA and IO muscles was measured with a two-dimensional ultrasonography device. Core endurance was assessed with prone bridge and sit-ups tests. Results: The assessments of the Pilates training group after the 6-week showed a statistically significant increase in the prone bridge and sit-ups test performances, and an increase in the thickness of the IO muscle [during resting in the supine position and abdominal drawing-in maneuver (ADIM) in standing position] and the TrA muscle (during ADIM in the standing position) (p < 0.05). Pilates exercises were also shown to have improved core muscle endurance and thickness (IO thickness during ADIM in the standing position and TrA thickness during resting in the supine position, ADIM in the supine and standing position) in the Pilates training group after a period of 18 weeks (p < 0.05). Conclusion: Pilates training has a favorable effect on the core endurance, and the TrA and IO muscle thickness of patients with Parkinson’s disease and this effect can be maintained until three months after the training.