This research studies the Arabic dialects mentioned in the book (The Characteristics) by Abu al-Fateh Uthman ibn Jinni (d. 392 AH). It begins with a brief introduction aimed at clearly and concisely distinguishing between the concepts of language and dialect. In this introduction, we refer to a precise and important issue that Ibn Jinni touched upon in this book: the issue of the disagreement among Arabs regarding their dialects. The introduction highlights his view toward those who claim the existence of this disagreement, whichserves as a pivotal entry point for understanding his methodology. This is followed by a core study of the research, which addresses the Arabic dialects mentioned in (The Characteristics), divided into two main sections to organize the scientific material and facilitate its review. The first section focuses on the words mentioned by Ibn Jinni, indicating that they are an Arabic dialect . These are arranged alphabetically to ensure easy reference and classification. The second section deals with the issues in which Ibn Jinni mentioned a number of Arabic dialects, also arranged alphabetically, similar to the first section. In both section, the research is careful to clarify Ibn Jinni's statement regarding each of these dialects separately, to explain his methodology in attributing those dialects to their speakers, and to reveal the variation in this attribution, whether through documentation or lack thereof. The research concludes with a summary that includes the most important findings and conclusions reached by this study in uncovering the Arabic dialectal material within the book (The Characteristics).