The paper introduces the invention of a type of light-aging instrument, the instrument's structure and its manufacture method. The instrument was used to conduct experiments on silk cloth using various light wave bands. The analysis of experiment data gathered from six groups of silk cloths found faint aging in several of the light wave bands. The experiment also discovered the relationship between the degree of aging on the surface of the silk and the intensity of the light. It provided an understanding of the aging effect of silk due to environmental temperature and humidity. This can be used as reference when lighting textile exhibitions.