Abstract Aim: To evaluate the effect of group reminiscence therapy (RT) as a nursing intervention on self-esteem and emotional wellbeing of older adults. Design: A quasi-experimental study. Methods: The study sample was composed of 50 older adults from the Geriatric social club in Zagazig City, randomly assigned into two groups. The reminiscence group received ten one-hour weekly sessions and the control group received only the routine club program. Pre- and post-intervention assessments were made using a self-esteem scale and emotional well-being dimensions (mental health continuum, emotion regulation, and satisfaction with life scale). Chi-square and Fisher’s exact tests, an Independent-samples t-test, and a paired t-test were used for data analysis. Results: The study findings showed that the group reminiscence therapy led to statistically significant improvements in reminiscence group self-esteem and all emotional well-being dimensions compared with the control group (p < 0.01). Conclusion: Group RT is effective in increasing self-esteem and improving emotional well-being in older adults. The study provides evidence to support the idea that reminiscence therapy is an effective and safe nursing intervention for improving older adults’ psychological well-being. Keywords: emotional well-being, group reminiscence therapy, older adults, self-esteem.