Background <p>Despite being largely preventable, the prevalence of Type 2 diabetes mellitus (T2D) is increasing rapidly in low- and middle-income countries, including India. Beyond biomedical risk factors, psychosocial elements such as disease knowledge and stigma play an important role in shaping treatment-seeking and social inclusion. However, limited evidence exists on how diabetes knowledge and stigma intersect within the Indian context.</p> Objective <p>This study aimed to examine the relationship between diabetes knowledge and multidimensional diabetes stigma among urban Indian adults.</p> Methods <p>A cross-sectional online survey was conducted among 210 adults (mean age = 31.33 ± 12.27, 74 females) in urban India. Participants completed validated measures of diabetes knowledge and diabetes-related stigma. Associations between knowledge, stigma dimensions, and sociodemographic variables were examined using correlation analyses, independent samples <i>t</i>-tests, and linear regression models.</p> Results <p>Higher diabetes knowledge was associated with greater stereotype-based and negative-attitude stigma. Familiarity with diabetes through a blood relative predicted higher knowledge and reduced social-distance stigma. Gender differences were observed, with men reporting higher social-distance stigma and women endorsing higher attitudinal and stereotype-based stigma.</p> Conclusion <p>Diabetes stigma in India is a multidimensional phenomenon shaped by knowledge, familiarity, and gendered social norms. While awareness and familial exposure may reduce interpersonal avoidance, they may simultaneously reinforce moralised and blame-oriented stigma. Stigma-reduction efforts should therefore move beyond information-based approaches to address structural, moral, and gendered dimensions of T2D stigma.</p>