Methylphenidate is a widely used stimulant for treatment of attention-deficit hyperactivity disorder (ADHD). In addition to core symptoms of attention and behavioral symptoms, methylphenidate is even effective for executive functions. However, abuse and misuse of stimulants, including methylphenidate, for the purpose of cognitive enhancement is an issue of concern worldwide. Some prejudices and misunderstandings against methylphenidate are popular ; however, little attention has been given to the neuropsychiatric evidence of methylphenidate for enhancement of cognitive function among healthy populations. In this article, our aim was to conduct a review of previous studies investigating the effect of methylphenidate in healthy populations. Findings from several recent studies have demonstrated the effectiveness of methylphenidate for enhancement of cognitive function in healthy populations. The mechanisms of cognitive enhancement are thought to be associated with motivation and the reward circuit in the brain. However, when considering the risk to benefit, an official discussion of the use of methylphenidate among healthy members of the population would be premature. Instead, investigation of epidemiological studies of the prevalence of misuse of stimulants among healthy members of the population, particularly adolescents and college students, is needed. In addition, based on achievements reported in previous studies, investigation of the effect of an approach using non-pharmacological enhancing motivation, which will in turn result in increased cognitive function would be helpful.