The purpose of the study was to determine the effect of insulin pen training using the Teach-Back method in older patients with type 2 diabetes (T2D) on their self-management of insulin treatment, quality of life (QoL), and glycated hemoglobin (HbA1c) levels. Participants included 25 patients in the intervention group, with a mean age of 80.76 ± 6.132 years, and 24 patients in the control group, with a mean age of 81.29 ± 4.920 years. All participants were older people who had previously been diagnosed with T2D, had been using insulin for at least 6 months, and lived in rural areas. Teach-Back pen training was provided to the intervention group, while general diabetes education was provided to the control group. One-way variance analysis, paired-samples t-test and independent sample t-test were used. The self-management of insulin treatment, QoL and HbA1c levels were determined before training and after 3 months. The study was conducted between December 2022 and April 2023. A significant difference was found in the mean scale scores between the intervention group and control group after training. The mean self-management of insulin treatment and QoL scale scores of the intervention group were significantly higher than those of the control group after training. The post-training HbA1c levels in the intervention group were lower than the pre-training levels. Teach-Back training improved diabetes self-management and QoL and decreased HbA1c levels in older patients with T2D living in a rural community.