Background <p>The outcomes of staff training programs regarding the effect of person-centered care in nursing homes as rated by their residents are limited. This study examines the effects of a nursing home training program by evaluating resident-rated person-centered care, comparing changes over time between an intervention group and a comparison group.</p> Methods <p>This quasi-experimental study was conducted in 25 nursing homes. A total of 124 residents in the intervention group and 65 in the comparison group were enrolled between August 2021 and June 2023. Data were collected using the ‘Person-centered Climate-Questionnaire-Patient version’ (twice, pre- and post-intervention). The two-year training program comprised knowledge and skills in quality of care through lectures, seminars, and skill practice among 15 managers and frontline staff members in nursing homes. These staff members were expected to implement what they had learned and diffuse their knowledge to their coworkers at their nursing homes. An ANCOVA analysis was performed with a significance level of <i>p</i> ≤ 0.05.</p> Results <p>Among the residents, the person-centered scores were statistically significant (<i>p</i> &lt; 0.001). The intervention group scores improved over time (mean = 13.6, SD = 20.0), whereas the comparison group declined (mean=-5.9, SD = 24.6).</p> Conclusion <p>The program was associated with improvements in person-centered climate as rated by residents. These findings highlight the clinical importance of training programs, including knowledge and skills in person-centered care, dementia care, teamwork, staff empowerment, and psychological nursing care, is central for improving person-centered care for nursing home residents.</p> Trial registration <p>Chictr.org.cnChiCTR2100048628. Registered July 12, 2021.</p>