BACKGROUND: Chronic ankle instability (CAI) presents neuromuscular control and functional performance difficulties. Although ankle-focused rehabilitation is widely practised, the relative effects of exercises targeting thoracic mobility and lumbopelvic stabilization in addressing CAI have not been thoroughly investigated. OBJECTIVE: The study aims to compare the effects of thoracic mobility and lumbopelvic stabilization exercises in patients with CAI. METHODS: The study was designed as a prospective randomized controlled clinical trial. A total of 30 participants (mean age = 31.93 ± 7.31; 21F/9M) who scored 27 points or on the Cumberland ankle instability tool voluntarily were enrolled in the study. The participants were randomly divided into two groups. In addition to the rehabilitation protocols, each participant was given a home exercise program, including ankle-strengthening exercises (3 times a week). The first group trained with thoracic mobility (TM), while the second group did lumbopelvic stabilization (LS) exercises under supervision twice a week for eight weeks. Participants’ pre and post-treatment assessments spanned an 8-week rehabilitation period, during which ankle and hip joint range of motion measurements were obtained using an electronic goniometer. Additionally, dynamic balance was assessed through the Y balance test, while ankle proprioception was evaluated using joint position sense measurements. The flexibility was assessed with an active straight leg raise test. RESULTS: Y balance, CAIT, and active straight leg raise test scores were improved in the eighth week in the thoracic mobility group (p< 0.05), while only active straight leg raise test and CAIT scores were significantly different in the lumbopelvic stabilization group (p< 0.05) according to intra group variables. In comparing the post-treatment scores between the groups, the thoracic mobility group had superior results in the joint position sense test for the right side of the hip and plantarflexion. (hip; TM: 70.71 ± 6.80, LS: 68.76 ± 5.50, plantarflexion; TM: 44.24 ± 7.28, LS: 38.30 ± 5.08). CONCLUSION: The findings suggest that while both interventions are effective in addressing various aspects of ankle instability, the thoracic mobility exercises may offer additional benefits, particularly in enhancing joint position sense, thereby providing valuable insights for the optimization of rehabilitation protocols for individuals with chronic ankle instability.