This study was necessary due to the increasing number of cases of natural disasters such as flood, air pollution, erosion, etc in Nigeria, particularly in the Abia state, as well as the accompanying psychological and health issues affecting individuals within families and society as a whole. The study aimed to examine the impact of rational emotive behavior therapy on farmers' post-traumatic stress (PTS) in Abia State, Nigeria. A randomized control trial was conducted in Abia state, with a sample size of 118 farmers with experiences of natural disasters. Two assessments were conducted before the treatment, immediately after the treatment, and 2 months later to evaluate PTS and irrational beliefs among the farmers. The treatment involved a self-developed PTS-focused rational emotive behavior therapy manual, consisting of 12 sessions lasting 60 minutes each, delivered by counseling psychologists trained in rational emotive behavior and family therapies. Data from the pretest, posttest, and follow-up test were analyzed using chi-square, percentage, partial eta squared, and analysis of covariance statistical tools. The results showed no significant gender differences in the socioeconomic status, employment, and debt status of the participants. The rational emotive behavior therapy was effective in reducing PTS caused by the flood among farmers. Gender did not have a significant moderating effect on farmers' experiences with PTS. The study suggested that family health specialists and rational-emotive therapists collaborate with local authorities to provide career counseling services to farmers and establish community-based rational emotive institutes in each state of Nigeria.