If the condition included in the contract is useless or impossible or illegal, the condition is void, but the contract is not void. Therefore, in the case where the contract stipulates that the party to the contract uses the subject and object of the contract in a forbidden act, in this case, without a doubt, this requirement is both forbidden and invalidates the condition. But there is doubt regarding the nullification of the marriage in this assumption. In this regard, a group of researchers believe that both the condition and the contract are invalid, while others believe that if the use of the contract is forbidden, only the condition is invalid, but there is no reason for the contract to be invalid. In the current research, which is based on the descriptive-analytical method, the conclusion has been reached that if the consumption of the subject of the contract is stipulated in the forbidden act, only the condition is invalid, but the contract itself is valid and valid.