OBJECTIVES: The CLOX (an executive clock drawing task) consists of an unprompted task that is sensitive to executive function (CLOX1) and a copied version that is more dependent on visuoconstructive function (CLOX2). This study aimed to explore the effects of age, education, and gender on the performance of the CLOX and to provide normative information on the test in the Korean elderly. METHODS: We administered the CLOX to 608 community-dwelling healthy volunteers aged 60-90, excluding people with serious neurological, medical, and psychiatric disorders, including dementia. Multiple linear regression analysis was performed to assess the relative contributions of the demographic factors to the CLOX scores. RESULTS: Education had a considerable influence on performance of both CLOX1 and CLOX2. Age and gender also had significant effect on both. There were significant interactions between education and gender for both CLOX1 and CLOX2. We also found interactions between education and age on CLOX2. Based on these results, we created normative data for the CLOX, stratified by age (60-74 and 75-90 years), education (0-3, 4-9, and 10+ years), and gender. CONCLUSION: Our normative data, based on a large, healthy elderly population, provides accurate reference information on CLOX performance and should be very useful for proper interpretation of CLOX scores in the Korean elderly.