This study aimed to find out if a bibliotherapy program had an effect on the ego-resilience of middle school students. Twenty-four second grade students from G middle school in G city who wished to participate in the bibliotherapy program were randomly assigned to an experimental and a controlled group. The experimental group had 12 sessions of bibliotherapy over six weeks, while the controlled group had none. The results of the study were as follows: First, the bibliotherapy program had a significant effect on the improvement of the overall ego-resilience of middle school students. Second, the bibliotherapy program had a significant effect on middle school students’ positive thoughts, problem solving skills, emotion control, and friendly behavior, among sub-areas of the ego-resilience. Integrating these study results, it was found that the bibliotherapy program in this study was effective for improving the ego-resilience of middle school students.