This article continues the series of articles of the author under the contract of sale of real estate. The article analyzes the subject of the contract of sale of real estate as an essential condition. First of all, the author joins the point of view of those authors who argue that the subject matter of the contract is on its nature and makes it possible to abandon the contract with a specific contractual type, and not the benefit that, by virtue of the contract, one party provides the other. However, for the purpose of considering the issues raised in the article, the subject of the contract of sale of real estate understands exactly the benefit that, by virtue of the contract, one party provides the other - real estate. Further, the article provides judicial practice on the classification of certain objects to real estate. The conclusion is made about the legal meaning of the fact that the notary confirmed contract with respect to the alleged real estate (according to the extract from the USRR), as well as in the legal process, it turns out that the subject of the contract is not relevant to the real estate. in the contract, in particular, in a situation where different documents are contained in the title document and the extract from the Register. And finally, the article concludes that the inconsistency of the subject of the contract of sale of real estate does not always entail the recognition of such a contract is not concluded.