Background <p>Vision impairment is a growing concern, with preventive eye health behaviors playing a critical role in reducing the risk of blindness. Although eye health behaviors among older Thai persons have been studied, existing programs often emphasize individual-level treatment and lack integration with behavioral change frameworks and community participation which limits their long-term effectiveness. This study aimed to evaluate the effectiveness of a community-based eye health promotion program in improving preventive eye health behaviors and vision-related quality of life among Thai older persons.</p> Methods <p>A cluster randomized controlled trial was conducted in four of seven villages, which were randomly allocated equally to either the intervention group receiving an 8-week eye health promotion program in addition to standard care or a comparison group receiving standard care. Each group included 100 participants who met the following inclusion criteria: 1) age ≥ 60 years; 2) visual acuity of ≥ 6/18 in the better eye; 3) no history of eye surgery or diagnosed eye diseases; 4) ability to communicate fluently in Thai; 5) reachable by telephone; and 6) willingness to participate. The intervention consisted of three components: community campaigns, behavioral promotion strategies, and social support enhancement. Data were collected at baseline, 8 weeks, and 12 weeks. Analyses were performed using <i>t</i>-tests and the Generalized Estimating Equations model.</p> Results <p>At 8 weeks, the intervention group showed a statistically significant improvement in preventive eye health behavior scores by 0.207 points (95% CI: 0.101 to 0.313, <i>p</i> &lt; .001), increasing further to 0.376 points at 12 weeks (95% CI: 0.281 to 0.471, <i>p</i> &lt; .001), compared to the comparison group. Vision-related quality of life also improved significantly, with a ^0.289-points increase at 8 weeks (95% CI: 0.232 to 0.347, <i>p</i> &lt; .001), and 0.369 points at 12 weeks (95% CI: 0.314 to 0.423, <i>p</i> &lt; .001).</p> Conclusions <p>Community-driven eye health promotion programs, facilitated by nurses and incorporating both individualized and group-based strategies, show potential to improve eye health behaviors and vision-related quality of life.</p> Trial registration <p>The research protocol was registered in the Thai Clinical Trials Registry (TCTR20231109002) (<a href="https://www.thaiclinicaltrials.org/show/TCTR20231109002">https://www.thaiclinicaltrials.org/show/TCTR20231109002</a>.) (Date of submission: November 9, 2023).</p>