Poor balance ability may contribute to shoulder pathology in patients with existing shoulder pathologies or vice versa. The relationship between kinesiophobia and chronic shoulder pain intensity has been researched, although the conclusions are conflicting. To our knowledge, no study in the literature explores the association between kinesiophobia and balance in patients with shoulder pain. To investigate the relationship between kinesiophobia, upper extremity functions, and balance abilities in patients with shoulder pain. Cross-sectional observational study. Physical medicine and rehabilitation hospital. Not applicable. A total of 44 patients with shoulder pain were included in the study. The pain severity was assessed using a visual analog scale (VAS). The Tampa Scale for Kinesiophobia (TSK), Berg Balance Scale (BBS), and Shoulder Pain and Disability Index (SPADI) were used to assess the patients. Ultrasound was used to diagnose underlying shoulder joint problems. Static and dynamic postural control was evaluated. The most common pathologies detected by ultrasound were supraspinatus tendinitis/rupture (77.3%), cortical irregularity (68.2%), and bursitis (63.6%). TSK score did not correlate with age, body mass index, symptom duration, or VAS score in rest (all p > .05), but it was associated with scores on the BBS (r = -0.437, p = .003), SPADI-pain (r = 0.474, p = .001), SPADI-disability (r = 0.355, p = .018), SPADI-total (r = 0.405, p = .006), and VAS in activity (r = 0.331, p = .028). According to multiple linear regression analysis, BBS score, SPADI-total score, and anterior-posterior sway length were significant predictors of TSK (r = 0.645, r2 = 0.416). According to the findings of this study, the main risk factors for high levels of kinesiophobia are poor balance, severe pain, and disability. In addition to mechanical causes of shoulder pain, diagnosing and intervening on underlying balance issues and psychosocial causes of shoulder pain will improve treatment success.