BACKGROUND: Dementia in China is increasingly burdensome yet remains underrecognized and undertreated due to low awareness and persistent stigma. Community-based strategies are urgently needed to address these barriers. By using real-world data from an 18-month dementia campaign in Wuhan, we retrospectively evaluated the feasibility and efficacy of opinion leader intervention (OLI), a novel, community-driven approach, in improving dementia knowledge, reducing stigma, and promoting screening among older urban adults. METHODS: Starting in August 2023, a three-phase campaign was launched, targeting 3550 residents aged ≥60 years in the Jiangdijie community, Wuhan. The pre-intervention phase (6 months) included monthly expert-led dementia education lectures at a senior center (30-60 attendees/session). The traditional intervention phase (next 6 months) involved distributing brochures in public areas and doubling lecture frequency. The final OLI phase (6 months) engaged 19 trained opinion leaders to disseminate knowledge, encourage screening, and model preventive behaviors during daily interactions. Free dementia screening was available throughout the campaign. Outcomes-dementia knowledge scores, stigma-related attitude scores, and screening participation rates-were assessed via samples randomly drawn from the elderly residents at the end of each phase (T0: n = 100, T1: n = 117, T2: n = 100). RESULTS: Dementia knowledge scores among older adults increased from 12.27 (T0) to 13.51 (T1), with a significant jump to 17.63 post-OLI (T2 vs T1, < 0.001). Stigmatizing attitudes scores improved from 2.11 (T0) to 2.43 (T1), rising further to 2.98 at T2 (T2 vs T1, = 0.010). Participation rates in dementia screening rose from 18.0% (T0) to 23.9% (T1), surging to 46.0% post-OLI (T2 vs T1, < 0.001). CONCLUSIONS: The OLI was associated with marked improvements in dementia knowledge, reduced stigma, and higher screening uptake compared with traditional health education methods. These findings highlight OLI's potential as a feasible strategy to enhance dementia awareness and care in Chinese urban communities.