This study aims to examine the relationship between pain and disability symptoms, somatosensory amplification, depression, anxiety, problematic personality traits, and quality of life in patients with Subacromial Impingement Syndrome (SIS). In the study, 100 cases diagnosed with SIS were evaluated using the Disabilities of the Arm, Shoulder, and Hand Questionnaire (DASH), Beck Anxiety Inventory (BAI), Beck Depression Inventory (BDI), Toronto Alexithymia Scale (TAS), Somatosensory Amplification Scale (SAS), SF-36 and Eysenck Personality Questionnaire (EPQ). There was a significant positive correlation between DASH scores and SAS (r=0.57, p<0.01), BAI (r=0.30, p<0.01), BDI (r=0.32, p<0.01), and TAS (r=0.33, p<0.01) scores whereas a significant positive correlation was found between BDAS scores and BAI (r=0.45, p<0.01), BDI (r=0.44, p<0.01), TAS (r=0.56, p<0.01) scores. Besides, DASH and SAS scores were significantly correlated with quality-of-life subscale scores (p<0.05). In Hierarchical Regression Analysis, only SF-36 subscales (physical function, bodily pain, mental health) were elucidated to have significant effects in explaining DASH scores (p<0.05), and only TAS scores were established to have significant effects in explaining SAS scores (p<0.05). Pain and disability symptoms are associated with quality of life in patients diagnosed with SIS when the effects of mental problems are controlled. Somatosensory amplification in patients with SIS is closely related to alexithymic symptoms considering the control of the effects of other mental problems and pain and disability symptoms.