Negation is a common phenomenon in languages and an important grammatical category. Based on the actual situation of diverse types of disposal prepositions in Modern Chinese and the wide use of the ″ba″ sentences， this article investigates into the negative disposal sentences taking the ″ba″ sentence as an example. According to the position of the negative word in the sentence， the Chinese disposal construction can be divided into two types: the negative word before the disposal preposition or the negative word after the disposal preposition and its object. There is a close relationship between the syntactic context in which the word ″ba″ is grammaticalized and the negative word pre- or post-positioned. The verb ″ba，″ in the sense of ″take/hold，″ is grammaticalized into the disposal preposition ″ba″ in the linkage structure. The semantic relation of ″ba″ linkage structure is generally more closely related so that the ″ba″ linkage structure is taken as a whole. The negative word appears in front of the linkage structure negates it totally. On the other hand， the linkage structure has two independent verb phrases.They have their relative independence in syntax. Therefore， negative words can also alone negate the second verb phrase of the ″ba″ linkage structure. But the situation rarely occurs. This phenomenon also strands in ″ba″ disposal sentence. It shows that the negative word can be placed before or after the ″ba″ in disposal sentence. But the negative word post-positioned examples occur less often than those of the pre-positioned negation. The scope and focus of negation also change along with the negative words' position. The scope of the pre-positioned negation is larger than that of those of the post-positioned negation. The focus of negation changes with the negative scope. The negative word in the sentence negates all its subsequent components， but the focus of negation is uncertain， as it can depend on the context. When the negative word is after the disposal preposition phrase， usually it is immediately before the verb. There is only one predicate verb and its related components （object or complement） in the scope of the negative word. The focus of negation can either be on the action itself， or on the object or complement which is after the predicate verb． In many cases the focus of negation depends on the speaker's or the narrator's pragmatic purpose. In other words， the negation scope of negative word and pragmatic factor are the important intrinsic motivation of the two kinds of negative disposal sentences which widely exist in Chinese dialects. The negative word is generally placed after the ″ba″ phrase in Chinese dialects， in Qinghai and Gansu， which have close contact with the languages of the Altai family. This phenomenon indicates that languages of the Altai family are influential in Chinese negative disposal sentences. Therefore， to study the changes of the syntactic structure of the Chinese negative disposal sentences， we have to explore the syntactic structure of Chinese itself. Meanwhile， we cannot ignore the influence of the alien languages． There are many issues worthy of further discussion on the Chinese negative disposal sentences. For example， the word order of the Chinese negative disposal sentences NP+Neg/Aux+PP+VP and NP+PP+Neg/Aux+VP are different from that of the other languages such as the English NP+Neg/Aux+VP+PP. The word order of the Chinese negative disposal sentences is unique in the word order types． 