Vagueness refers to the form of expression that has an open range of interpretations. Certainly, a research paper begins with an abstract. The abstract should be a self-contained piece of information, clear, concise, brief, comprehensive, precise, and to the point. The problem of the present study focuses on the reasons behind using vague words or expressions in writing research abstracts. The current study aims at identifying vagueness in research abstracts used by researchers. The researcher has analysed two abstracts following Kempson’s (1977) model of vagueness. The model is based on four types of vagueness: referential vagueness, indeterminacy of meaning, lack of specification in the meaning of an item and disjunction in the specification of the meaning of an item. The abstracts are taken from “College of Basic Education Researches Journal”, Iraq; and “AL-Kitab Journal for Pure Sciences”, Iraq before being reviewed and published. The results of the study show that the researchers used 8 cases of vagueness for the sample of the study. Referential vagueness scored the percentage (50%), the indeterminacy of meaning and lack of specification in the meaning of an item (25%), and finally, no cases of disjunction in the specification of the meaning of an item were found. To sum up, it has been concluded the reason behind using vague words or expressions in writing abstracts due to the lack of knowledge about vague expressions and using imprecise words. Also, the reason behind using vague words or expressions in writing abstracts attributed to misuse of punctuation marks.