Background: In Sweden, core treatment for osteoarthritis is offered through a Supported Osteoarthritis Self-Management Programme (SOASP), combining education and exercise to provide patients with coping strategies in self-managing the disease. The aim was to study enablement and empowerment among patients with osteoarthritis in the hip and/or knee participating in a SOASP. An additional aim was to study the relation between the Swedish version of the Patient Enablement Instrument (PEI) and the Swedish Rheumatic Disease Empowerment Scale (SWE-RES-23). Methods: Patients with osteoarthritis participating in a SOASP in primary health care were recruited consecutively from 2016 to 2018. The PEI (score range 0-12) was used to measure enablement and the SWE-RES-23 (score range 1-5) to measure empowerment. The instruments were answered before (SWE-RES-23) and after the SOASP (PEI, SWE-RES-23). A patient partner was incorporated in the study. Descriptive statistics, the Wilcoxon's signed rank test, effect size (r), and the Spearman's rho (r(s)) were used in the analysis. Results: In total, 143 patients were included in the study, 111 (78%) were women (mean age 66, SD 9.3 years). At baseline the reported median value for the SWE-RES-23 (n = 142) was 3.6 (IQR 3.3-4.0). After the educational part of the SOASP, the reported median value was 6 (IQR 3-6.5) for the PEI (n = 109) and 3.8 (IQR 3.6-4.1) for the SWE-RES-23 (n = 108). At three months follow-up (n = 116), the reported median value was 6 (IQR 4-7) for the PEI and 3.9 (IQR 3.6-4.2) for the SWE-RES-23. The SWE-RES-23 score increased between baseline and three months (p <= 0.000). The analysis showed a positive correlation between PEI and SWE-RES-23 after the educational part of the SOASP (r(s) = 0.493, p < 0.00, n = 108) and at follow-up at three months (r(s) = 0.507, p < 0.00, n = 116). Conclusions: Patients reported moderate to high enablement and empowerment and an increase in empowerment after participating in a SOASP, which might indicate that the SOASP is useful to enable and empower patients at least in the short term. Since our results showed that the PEI and the SWE-RES-23 are only partly related both instruments can be of use in evaluating interventions such as the SOASP. Trial registration: ClinicalTrials.gov. NCT02974036. First registration 28/11/2016, retrospectively registered.