Upper-limb paresis is a main disabling condition in stroke and neurological diseases and rehabilitation is essential for recovering/maintaining function. Upper-limb weight support may help/enable these patients performing movements against gravity thus allowing for task oriented interventions. In this framework, an exoskeleton for upper-limb weight support was developed. In this preliminary study the system was tested in a small group of neurological patients (N = 12) to verify the overall usability and its efficacy in assisting patients during functional movements against gravity. Patients performed some functional tasks of the ARAT test both with and without the exoskeleton. The system seems effective as it enabled even the most impaired patients performing the tasks. All patients could wear the exoskeleton and complete the tasks. Usability of the system was assessed as adequate for a use inside a clinical study. Future work will focus on verifying the efficacy of task-oriented intervention performed using the exoskeleton.