Catechisms are books that describe people's behavior towards each other, society and Allah Almighty, as explained by the Islamic religion. They give basic religious information that regulates our daily life and worship. It is the duty of every Muslim to know the provisions of Islam regarding faith, worship and daily life. The legal principles necessary for a Muslim life have been learned through catechism books. The legal rules stated in these books form a part of a whole, together with the religious and moral rules that affect people's social life. Therefore, one of the most important resources for those who want to get to know the mentality - self-expression style - worldview - in short, the nature of the people living in these lands are catechism books. Ömer Nasuhi Bilmen (d. 1971) is a name that recent scholars agree on regarding his scientific virtue and moral superiority. The Great Catechism of Islam that he prepared has been printed in millions of copies in the last fifty years. The demand it receives from the reader results in the conclusion that it responds to society's needs in this regard. The work is based on the belief of Ahl al-Sunnah. Fiqh rulings have been extracted from reliable sources. It has been prepared in a way that people can easily understand, taking into account daily needs. The late Ali Fikri Yavuz Hodja's simplification, which remained faithful to the meaning of the text and enabled today's generations to understand it better, continued to increase the demand for the Great Islamic Catechism. The path we follow as Samarkand Publishing is as follows: The simplified version of the book has been preserved exactly as it is - except for sentence corrections in a few places, the language and style have not been interfered with. Where clarification is deemed necessary, an explanation note has been included in the form of footnotes and with serial numbers. At the end of the explanations, relevant resources are also included when necessary. An extensive list of the source works we used in our review is also added at the end of the book. In this way, it is intended to help our diligent readers who want to get to know the source books. All necessary technical facilities have been used to make the book understandable and present it to our readers in a beautiful printing. Effort is from us - success is from Allah Almighty. Pages: 624 Cover: Hardcover Size: 17 x 24 cm