Throughout the different eras of Islam, the phonologists have contributed in enriching the Arabic grammar with immense benefits and researches by their deep studies to the Holy Quran and its rules and pronunciation. One of them was the Omani scholar Abu Mohamed, Al Hassan bin Ali bin Said, who lived in the end of the fourth century and the beginning of the fifth century, according to the Hijri calendar. He was able to do so through a number of books, and the most important of them . (The Middle Book of Pronunciation) ( الكتاب الأوسط في علم القراءات ) was The purpose behind selecting the above mentioned book is to study the grammatical endeavours by Omanis. My research started with an introduction summarizing my justifications of choosing this topic, and one of the most important of them was serving the Holy Quran through selecting a topic that deals with its rules and pronunciation. I have also highlighted the method of research and the important chapters that this research covers. Then I involved in the preamble which I divided into two researches, one talks about Abu Mohamed's autobiography, his study journey and his research career and polite literature. The second part deals with (The Middle Book of Pronunciation) and its main studies and its characteristics. The research is divided into three chapters, as the following: The First: with the title (the grammar issues in the book) and it discuses two major themes, the first: Grammar Controversy and the second: the author's choices and his interpretations. The second: with the title (The grammar resources in the book) The Third: titled (the method of the book) and it covers two researches. The first is "the Grammatical Concepts" and the second is "the Grammatical evidence in the book. Finally the research ended with a conclusion that sheds lights on the results and the recommendations.