The purpose of this study was to explore the effectiveness of a training program based on the metacognitive skills in improving problem-solving skills in the female students of eighth-grade. The sample consisted of (60) female students of eighth-grade with age mean (14.3 yrs.). Quasi experimental design was used in this study. To test study hypotheses, five tools were developed : the training program based on the metacognition skills, problem-solving scale, the scale of metacognition skills , self-assessment questionnaires of the sessions, , and an observation card. Findings of this study showed that the training program based on metacognitive skills was effective in improving problem-solving skills in the eighth-grade female students; that is, these findings revealed that there where significant differences between experimental group and control group in problem – solving skills in favor of the experimental group. In the light of these findings; a set of recommendations and suggestions were made.