Objectives <p>Emotional perceptions of ageing are heterogeneous, and the specific mechanisms between these perceptions and health promotion lifestyle remain unclear in older people with diabetes. We characterized emotional perceptions of ageing profiles and explored the associations between profiles, frailty, and health promotion lifestyle, with frailty as a potential mediator.</p> Methods <p>A cross-sectional study was conducted on 200 older adults with diabetes. Sociodemographic, emotional perceptions of ageing, frailty, and health promotion lifestyle variables were measured. Different profiles of emotional perceptions of ageing were identified by latent profile analysis using Mplus 7.4. SPSS 25.0 was employed for descriptive, regression, and mediation analyses.</p> Results <p>Two profiles of emotional perceptions of ageing were identified: high ageing emotional acceptance (78%) and low social connectedness (22%). Those with low social connectedness demonstrated significantly higher frailty and lower health promotion lifestyle (<i>p</i> &lt; 0.05). Frailty played a significant mediating role in the relationship between emotional perceptions of ageing and health promotion lifestyle (<i>β</i> = −1.704, 95% confidence interval: −3.766, − 0.112).</p> Conclusion <p>The connotation of emotional perceptions of ageing emphasizes social connectedness and ageing emotional acceptance. Low social connectedness were associated with deteriorated health promotion lifestyle through higher frailty. Older adults with diabetes characterized by low social connectedness require urgent attention. Routine assessment and management of frailty should be considered as a key point of daily care to promote the healthy ageing lifestyle.</p>