Recently, in Korea the birthrate is declining and the average life span has been increasing. Thus, compared to the previous periods nowadays, older people are required to work. Even elderly people are rejoining the workforce. Korean companies set the retirement age between 55 and 60 years of age, however, accidents occur frequently. Thus, it becomes necessary to evaluate the ability of the elderly person. Since the required function of the worker varies from job to job the evaluation of the capability must also be conducted according to the desired functions. One of the methods used in this study is the continuous control knob to evaluate the tracking control ability to investigate the relationship of manual dexterity and age. The result of the study Indicates that the manual dexterity decreases with age. However, there are differences among individuals. The individuals lifestyle affected the manual dexterity of that individual. As a result, a company may use the manual dexterity as an measure to evaluate the elderly persons work ability.