Background <p>Social support is essential for the self-management of type 2 diabetes mellitus (T2DM); no specific measure of the quality of social support has been designed and tested for people with T2DM. Having a validated questionnaire that is culturally and linguistically appropriate in this field would nurture research in this area and contribute to better patient health outcomes.</p> Aims <p>This study investigated the psychometric features of the Autonomy in Relatedness Inventory (ARI) among individuals with T2DM in Jordan.</p> Methodology <p>We used a secondary dataset on self-management and outcomes of individuals with T2DM to examine the psychometric properties of the ARI. The ARI’s items’ overall reliability was assessed using internal consistency (Cronbach’s alpha). Exploratory Factor Analysis (EFA) was used to evaluate the validity of the ARI. Confirmatory factor analysis (CFA) was performed using structural equation modeling (SEM) to test the yielded factors.</p> Results <p>The ARI demonstrated high reliability (Cronbach’s alpha value was 0.90) and validity in T2DM patients. Convergent validity of the ARI was established. The findings showed that ARI was strongly correlated with functional social support (<i>r</i> = .61, <i>p</i> &lt; .001), in addition to negative correlations with depression (<i>r</i>= -.26, <i>p</i> &lt; .001), anxiety (<i>r</i>= -.18, <i>p</i> &lt; .001), and stress (<i>r</i>= -.24, <i>p</i> &lt; .001). Regarding the factor structure of ARI, two latent factors were determined using a scree plot and EFA.</p> Conclusion <p>ARI provides a psychometrically sound method for measuring autonomy and relatedness in T2DM patients in Jordan.</p> Clinical trial number <p>Not applicable.</p>