Abstract: The light transmissivity of an object is the ratio of transmission intensity to incident intensity. Based on the formula of the unit transmissivity, t=\sqrtnT, the two quantitative measuring and grading methods of photometer and light column are introduced in the paper. Jadeite jade samples with different transparency are observed and measured. The results show that the transparency grading of jadeite jade samples could be estimated according to the lengh (l value) and characteristics of the light column produced by the light for basically achieving the grading demand of the transparency of jadeite jade jewelry. At the same time, the measuring equipment is simple for taking and can be easy to be popularized in the jadeite jade market.