Vitamin D deficiency is highly prevalent in the general population and is associated with various chronic health conditions. In addition to its role in bone mineralization, Vitamin D has various physiological effects that may impact the pathogenesis of shoulder pathologies. Vitamin D deficiency may also affect outcomes after shoulder surgeries, such as rotator cuff repair and total shoulder arthroplasty. Vitamin D plays a role in tissue healing, bone growth, and maintenance of homeostasis in skeletal muscle cells. Vitamin D also has anti-inflammatory effects that are important to rotator cuff health. Vitamin D deficiency is highly prevalent in patients with rotator cuff tears, suggesting its role as a potential risk factor. Vitamin D deficiency has been associated with decreased preoperative shoulder strength as well as increased re-tear rates, postoperative stiffness, and the need for revision surgery in patients who underwent rotator cuff repair. Studies have also demonstrated a potential association between vitamin D deficiency and increased risk of revision after total shoulder arthroplasty. Further research is necessary to elucidate the direct role of vitamin D in the pathogenesis of rotator cuff tears and its impact on clinical outcomes after rotator cuff surgery and total shoulder arthroplasty.