Abstract: We stated the normal assessment of cleaner production, especially the definition, the principle, the content and the pattern of the fuzzy math. A scientific method for qualitative evalution and management of clearner production was provided in this paper. It shows that fuzzy math assessment can assess every key links' situation in the factory, discern the chances of cleaner production and find out the weakest link of cleaner production. It also can comprehensive and exactly assess the entire factor which effect the quality in cleaner production and can transform the undetermined and complicated factors to the simple and quantity assessment pattern. Moreover, we give an using example of a food processing industry and takes great achievements.