The establishment of evaluation test method of the titania photocatalyst fine particle impact to human body skin was attempted. In this method, the amount of emergence of carbon dioxide, which was expected one of the generation products from the artificial skin according to the titania photocatalyst fine particles activity, was identified and measured by the gas analyzer. It was found that the amount of the carbon dioxide evolution from the artificial skin was different according to the difference of the particle size of the titania photocatalyst fine particle.