Aim: Acromioclavicular joint (ACJ) disorders are particularly common in patients with impingement syndrome. We aim to evaluate the effectiveness of corticosteroid (CS) injections and pulsed radiofrequency (PRF) therapies applied to the Acromioclavicular joint (ACJ) and the subacromial area in the long-term in patients with impingement syndrome. Material and Method: 40 patients were analyzed in 2 different groups; CS(n=20) and PRF(n=20). Pre-treatment (W0) and post-treatment follow-ups at one (W1), four (W4), 12 (W12) and 24 weeks (W24) were carried out using Visual Analogue Scale (VAS), Shoulder Pain And Disability Index (SPADI) scores and Beck Depression Inventory (BDI) Scale tests. Results: There was a statistically significant improvement in all the evaluation parameters at W1, W4, W12, and W24 compared to W0 in both groups (p<0.05). The comparison of the groups with each other there was no statistically significant difference between the VAS, SPADI and BDI values at W1, W4, W12, W24 (p>0.05). Discussion: Our study results showed that CS injections and PRF therapy applied to the ACJ and subacromial area were effective during six-month follow-up in patients with chronic shoulder pain due to impingement syndrome. But statistical significance superiority to each other was not determined.