Enthesitis is the key pathological lesion in the spondyloarthritides group and an important element for early diagnosis with a predictive and prognostic value. The recognition of enthesitis on a clinical basis alone remains a challenge and creates unnecessary delays in diagnosis and adequate treatment commencement. Musculoskeletal ultrasound is a valid, reliable, and feasible imaging tool valuable for identifying inflammatory and structural lesions at enthesis level, helpful in establishing a diagnosis, evaluating disease activity and therapy monitoring. This paper focuses on the most relevant aspects of current literature regarding enthesitis and highlights the musculoskeletal ultrasound added value in enthesis assessment.