一份生效的工程合同具有法律约束力,是合同履行及争议处理的依据,是承包人全过程索赔的基本依据。那么无效合同该如何结算呢?工程合同应具备双方主体合格、工程确定合法、意思表示真实、内容不应违法、符合法定程序等五个要件之后才能生效。如果工程合同不具备该五个条件之一,就会出现合同效力待定、合同可撤销甚至合同无效等法律后果。在工程实践中,问题比较突出的是合同无效 An effective contract is legally binding and is the basis for contract performance and dispute settlement. It is the basic basis for the entire process of the claimant’s claim. So how to settle the invalid contract? Engineering contract should have the main body of both parties, the project is valid, the meaning is true, the content should not be illegal, in line with legal procedures and other five elements to take effect. If the engineering contract does not have one of the five conditions, there will be legal validity of the contract to be determined, the contract can be revoked and even invalid the contract and other legal consequences. In engineering practice, the problem is more prominent is the contract is invalid