The requirements for an agreement to have legal effect are: (1) the parties to the agreement have the corresponding ability to conclude an agreement; The subject of conclusion should be a qualified person with civil capacity, including natural person, legal person, etc., who can correctly understand the content of his own behavior, can freely control his own behavior, and can sign relevant agreements in his own name. (2) The parties to the agreement express their will voluntarily and truthfully; The parties to the agreement must be two or more parties, not one party, and must be negotiated on an equal and voluntary basis.
 (3) The contents of the agreement do not violate the mandatory provisions of laws and public order and good customs.
 The agreement between the two parties shall comply with the law and shall not harm the public interest.
 An agreement established in accordance with the law shall come into force when it is established, but if it is otherwise provided by law or agreed by the parties, it shall come into force when the prescribed or agreed conditions are met.
 Legal basis:
 Article 143 of the Civil Code of the People's Republic of China
 Civil juristic acts that meet the following conditions are valid:
 （1） The actor has corresponding civil capacity;
 （2） True declaration of intention;
 （3） It does not violate the mandatory provisions of laws and administrative regulations, and does not violate public order and good customs.
 Article 502 of the Civil Code of the People's Republic of China
 A lawfully formed contract shall become effective upon its formation, except as otherwise provided by law or agreed by the parties. Where, in accordance with the provisions of laws and administrative regulations, a contract shall go through the formalities of approval, etc., such provisions shall apply. Failure to go through approval and other procedures that affect the effectiveness of the contract shall not affect the effectiveness of the obligation clauses in the contract such as performance of approval and relevant clauses. If the party who should go through the formalities of application for approval fails to perform its obligations, the other party may request it to bear the responsibility for breach of such obligations. In accordance with the provisions of laws and administrative regulations, the provisions of the preceding paragraph shall apply to the change, transfer, dissolution and other circumstances of a contract where approval and other formalities shall be handled.