One of the risks that the gifted students are confronted with is underachievement. This is a surprising fact for those with higher abilities. Underachievers can be found in every grade in school, from kindergarten to graduate school, in both sexes, across ethnic and socioeconomic groups, and in every occupation. What is underachievement? Underachievement is a discrepancy between ability and performance that persists over time. Many researches on the gifted education show the main reasons for the underachievement of the gifted are as follow: emotional problems of the gifted, their peer groups, lack of proper education satisfying their needs, learning disabilities of the gifted, and lack of differentiated and individualized curriculum. This is a literature review on the possible causes of underachievement and ways to eliminate underachievement of gifted children.