Children and adolescents require a greater range of elbow motion in comparison to adult population to achieve functional and contemporary tasks. For this reason, paediatric elbow stiffness should be correctly addressed. Causes of elbow stiffness in paediatric population are numerous and can be classified into three main categories: post-traumatic, congenital and acquired. The most common cause of stiffness is post-traumatic injury; it includes fractures and malunion, burns, head injury and elbow surgery. Atraumatic aetiologies include inflammatory joint disease, infection, metabolic disease, haemophilia and congenital conditions. Congenital causes of stiff elbow are rare disorders, such as arthrogryposis multiplex congenita, Beals and Larsen syndromes and congenital radial head dislocation and radio-ulna synchondrosis. Also, the spastic cerebral palsy alters the functional elbow motion with spastic flection and extension contraction, supination and pronation spastic deformities. The anatomopathological classification identify the four categories of elbow stiffness: intra-articular, capsular, extra-articular and neurological. The treatment of stiffness elbow starts with non-operative treatment: ice, heat, supervised physical therapy, active exercises, electrical stimulation and splinting. Closed manipulation under anaesthesia can be a valid option. Surgical treatments include arthroscopic and open capsular release.