Background Hand osteoarthritis (OA) is one of the most prevalent musculoskeletal diseases in an adult population and may have a large influence on an individual’s functioning, health-related quality of life and participation in society. Several studies have demonstrated that exercises may reduce pain and improve functioning in people with knee OA, with a similar effect suggested for hip OA. For hand OA, available research is very limited and shows conflicting results, and high-quality randomised controlled trials are warranted. This paper outlines the protocol for a randomised controlled trial that aims to determine the effect of an exercise intervention on self-reported hand activity performance in people with hand OA. Methods Participants with physician-confirmed hand OA according to the ACR clinical criteria are being recruited from two Norwegian OA cohorts: the population-based “Musculoskeletal pain in Ullensaker Study” (MUST) OA cohort, and the hospital-based Oslo Hand OA cohort. Participants are randomised into an intervention- or control group. The control group receives “usual care”, whereas the intervention group receives a 12-week exercise intervention. The intervention group attends four group sessions and is instructed to perform the exercise program three times a week at home. Adherence will be captured using self-report. During the eight weeks with no group sessions, the intervention group receives a weekly telephone call. The assessments and group sessions are being conducted locally in Ullensaker Municipality and at Diakonhjemmet Hospital, Oslo. Outcomes are collected at baseline, and at 3 and 6 months. The primary outcome measure is self-reported hand activity performance at 3 months post-randomisation, as measured by the Functional Index for Hand Osteoarthritis (FIHOA); and a patient-generated measure of disability, the Patient-Specific Functional Scale (PSFS). Secondary outcome measures are self-reported OA symptoms (e.g. pain, stiffness and fatigue), the Patient Global Assessment of disease activity, measured hand function (e.g. grip strength, thumb web space and hand dexterity) and health-related quality of life. Cost-utility and cost-effectiveness analyses will be conducted. Discussion This study will contribute to the knowledge on both the effect and resource use of an exercise programme with telephone follow-up on self-reported hand activity performance among people with hand OA. Trial registration The trial is registered at ClinicalTrials.gov with registration number: NCT01245842 .