Metacarpophalangeal pattern profile (MCPP) was analyzed in 14 Japanese children (mean age 6.7 years old) with Sotos syndrome. The patients were divided into 2 groups based on age; group 1 (n = 8): 6 years or over; group 2 (n = 6): less than 6 years. The mean values of standard deviation of the 14 patients with obviously large hand were all above 1.4. The MCPP in group 1 showed (1) two major peaks in metacarpal and proximal phalangeal areas, (2) a small peak in middle phalangeal area, and (3) relatively short distal phalangeal bones compared with the metacarpal and proximal phalangeal bones. The MCPP in group 2 was similar to that in group 1, but an additional peak was observed in distal phalangeal area. The MCPP of Japanese patients showed a quite similar pattern to that of Caucasian patients, and we conclude the method can also be a useful tool in the diagnosis of the Japanese patients. In correlation study, 8 of the 14 patients had a significant positive correlation, but 2 patients in group 2, less than 3 years, had no positive correlation. We suggest the method is not applicable to young patients less than 3 years.