There is ample evidence that African Americans and Hispanic Americans demonstrate lower scores on widely used neurocognitive tests, compared to non-Hispanic Caucasians. However, there is a scarcity of empirical data for Asian Americans. This study aimed to examine cognitive test performance of one of the Asian American subgroups : Japanese Americans. Seventy-one Japanese Americans (JAs) and 71 Caucasian Americans (CAs), ages between 45-91, participated in the study. The Boston Naming Test-2 (BNT), San Diego Odor Identification Test (SDOIT), Controlled Oral Word Association test (COWA-FAS), category fluency test (Animal Fluency), California Verbal Learning Test (CVLT), California Odor Learning Test (COLT), and Brief Visuospatial Memory Test-Revised (BVMT-R) were administered. We collected data on levels of acculturation, quality of educational attainment (Wide Range Achievement Test-4 Reading and Math Computation subtests), bilingual status, and generation status in the U.S. There were no significant differences between the two ethnic groups on the battery of neuropsychological tests. However, the two groups showed somewhat different patterns in the associations between the test performance, and age and gender. JAs tended to show a stronger age-score relationship on the BNT, SDOIT, BVMT-R total recall, and COLT total recall. With regard to gender, JA men tended to score lower than JA women and than CA men on CVLT Trial 5. Additionally JA men tended to score lower than JA women on the CVLT Long Delay Cued Recall. When the raw scores of the JAs were converted into demographically corrected scores using the Caucasian norm, JAs had more measures that yielded larger "impairment" rate compared to theoretically driven rate (15.6%) compared to Caucasian Americans. The second-generation JAs showed a much larger proportion of "impaired" compared to the third-generations, on the BVMT-R Total Recall and BVMT-R Delayed Recall. The results indicated that some neuropsychological test results need to be interpreted with caution in the older JAs, at least until culturally appropriate norms become available. Future studies are needed to investigate if this pattern would persist in the succeeding generations, and in the descendants of the post-war immigrants from Japan.