The relationship of description logic ALNUI and ER model is analyzed, especially how to translate ER model into ALNUI knowledge bases for reducing the reasoning on ER model to model reasoning on ALNUI knowledge bases is investigated, and the problem of fuzzy ER modeling with description logic is further studied. Aiming at the characteristics and requirement of fuzzy ER model and based on the description logic ALNUI, the description logic ALNUI is generalized through fuzzy logic. And a kind of new description logic, i.e., fuzzy description logic FALNUI (fuzzy ALNUI), is presented. The fuzzy ER modeling with description logic FALNUI is studied to translate fuzzy ER model into FALNUI knowledge bases. The reasoning problem of satisfiability, redundancy, and subsumption relation of fuzzy ER model may reason automatically through reasoning mechanism of fuzzy description logic FALNUI, and the correctness of these reasoning problems is proved.