Recently a relationship between serotonin transporter transcriptional control region (5-HTTLPR) polymorphism and anxiety related personality traits in Caucasians was reported. We performed PCR of DNAs from the blood for determining the 5-HTTLPR genotypes of 191 Japanese subjects, which were medical staff and students, and obtained Revised NEO Personality Inventory (NEO-PI-R) and the Temperament and Character Inventory (TCI) in 144 subjects. The association was analyzed by one-way ANOVA. The present study demonstrated that allelic frequency of 5-HTTLPR (s allele frequency was 0.785) in our subjects was considerably different from that in Caucasians. No significant differences were found in the anxiety-related personality traits among genotypes, while cooperativeness in TCI showed a significant difference among genotypes. The property of 5-HTTLPR may not be reflected directory on the personality inventories.