Agni Purana has been divided into three eighty three chapters. The various adhyayas or chapters in this Purana deal with a number of topics. The very first chapter begins with a customary salutation. It is a conference between Suta and Sanaka. Suta has volunteers a narration of the Agnipuram as disclosed to him by Vyasa who in turn had learned it from Vasistha. It also deals with the incarnations of Lord Vishnu.

Chapters two to six and the sixteenth chapter also deals with the incarnations of Lord Vishnu. They discuss about Matsya, Kurma and Varaha and the sixteenth chapter talks about Lord Buddha and Kalki Avatar. The Adhyayas five to eleven describe all the seven kandas or episodes of Ramayana. The twelfth chapter of Agni Purana has described the summary of Harivamsha. The thirteenth and the fourteenth chapter have brought forth the story of Mahabharata.

The essential characteristics of Purana have been described in the chapters 17 to 20 of Agni Purana. A large portion of the Purana deals with the Hindu modes of worship. They are chapters 21 to 70. These chapters have incorporated a discussion between Narada, Lord Agni, Hayagriva and Bhagvan. The chapters deal with religious bathing, construction of a Kunda, the various mudras of worship, the mode of worship of Vasudeva, Sankarshana, Pradyumna, and Aniruddha, consecration of an image, architecture of a temple, iconography of the images, the worship of Salagrama, the rules for the installation of the images and repair of a temple. Chapter 71 has described the worship of Lord Ganesha. On the other hand adhyayas 72 to 105 has discussed the worship of Linga and the various forms of Devi. Methods of establishing a sacrificial fire, Canda Worship, worship of Kapila Devi and the consecration of a Temple is also a part of these chapters of Agni Purana.

There are certain chapters in the Purana which have been dedicated Vastu, creation of Swambhu, Bhuvan Kosha, and description of Tithas and also a detailed description of ancestral rites. Some of the adhyayas in Agni Purana have also dealt with the geography, astronomy and astrology of India. There are chapters in the Agni Puran which gives detailed description of the duties of various Varnas in the society.

Adhyayas or chapters in the Agni Purana also discuss various state as well as religious gifts. They have also dealt with statecraft, archery and weapons associated with it. Some of the adhyayas in Agni Purana have also discussed about many of the Puranic dynasties.

The chapters towards the end of Agni Purana deal with various branches of medicines. Some of the chapters deal with the worship of Lord Surya and various mantras. Certain chapters in the Puran have talked about the necessity of establishing a Linga in the temple. Adhyayas in the Agni Purana have discussed the various Pingala sutras and have also discussed the four ways of displaying emotions. There are also chapters in the Purana which have been dedicated to grammar for instance chapter 349 to 359 have talked about Chandra Vyakarana.

Some of the concluding chapters have dealt with Raja Yoga and Hatha Yoga and the knowledge of Brahma. Adhyaya 381 has described Bhagavad Gita, chapter 382 consists of a version of the Yama Gita and finally the last chapter of Agni Purana has concluded describing in detail the glorification of the Purana.