This paper inductive and descriptive approach, to monitor the role of Omani heritage in the lexical industry until the end of the thirteenth century AH, by standing on the main axes dealing with the Omani lexical production, the motives of lexical authorship, and the importance of these lexical efforts. The importance of the study is due to the fact that it sets a general framework for the Omani lexicography and opens new research horizons, the most important of which is the achievement of the Omani manuscript lexical output.