One of the most important economic issues that has a lot of use in law systems, especially in the Iranian law system, is the issue of blasphemy. There is always a difference of opinion among jurists regarding the nature of reward, that reward is a contract with a unilateral juridical act. Some have considered it as a unilateral juridical act' and some have considered it as a contract. In civil law, the nature of the contract is not clearly stated, but the contract is introduced as one of the specific contracts, and in the seventh chapter of this law, articles 561 to 570 are related to this issue. Assigned therefore, it is important to know the law nature of reward in terms of the conditions of realization and the effects and rulings that follow it. The purpose of the current research is to identify the nature of blasphemy in Iran's legal system. In the present study, which is using descriptive and analytical methods, we analyze the nature of the contract in the Iranian law system. The findings of the research show that the nature of the contract is the contract, because the agent decides with his own intention and consent to perform the contract. Therefore, it cannot be considered that the reward was concluded with only one will and the same thing. It excludes reward from the number of occurrences.