In the present study a 16 week comparison study was conducted of behavioral, cognitive and educational measures in school-age Taiwanese children with attention-deficit hyperactivity disorder (ADHD) receiving open-label methylphenidate (MPH). Subjects include 14 male and five female ADHD children. They received MPH twice per day continuously for 16 weeks. Measures of behavior, cognitive function (Wisconsin Card Sorting Test, Tower of London and Continuous Performance Test), Chinese and arithmetic learning achievement were compared with those of their baseline condition. After MPH, 68-78% of children showed improving behavior in classroom and at home. Among the neuropsychological tests, only the percentage of preservative error was improved (P = 0.022). Approximately 61-66% of children had improvement in academic learning (P = 0.013 for Chinese, 0.004 for arithmetic). The MPH treatment demonstrated improvement in domains of classroom/home behaviors and academic performance, but showed minimal change on neuropsychological functioning in Taiwanese ADHD children. The finding of academic gain was unexpected, which might be due to the greater interest in achievement and better compliance to cultural expectations by Taiwanese versus Western students, which translated into more rapid improvement in academic performance.