Abstract: The concept of fuzzy bag automata and fuzzy bag language are introduced; the state transition diagram of fuzzy bag automata is given, the structural properties of fuzzy bag language repectitive sequence are discussed in the state transition diagram of fuzzy bag automata; the relation between Chomsky’s grammatical fuzzy languages and fuzzy bag language is put forth. Pointed out also is the inclusion relation among the class of fuzzy regular language, the class of fuzzy bag language and the class of fuzzy context-sensitive language, and the crossing-relation between the class of fuzzy bag language and the class of fuzzy context-free language.