China's " Law of Succession" promulgated and implemented in 1985, based on China's social reality, stipulates its testamentary succession system. However, there is no legal provision related to the common will in the “Law of Succession”. The only provision concerning the common will is Article 15 of the “Detailed Regulation on the notarization of the will” promulgated by the Ministry of Justice in 2000. According to the provisions of Article 15, the notary office does not support the establishment of a common will between the parties, but requires the parties who insist on the establishment to clearly stipulate the conditions for go into effect, change and withdrawal of the will. Due to the contradiction between the actual existence of the common will and the lack of law, the trial of the people's court fell into a difficult situation that could not be relied upon, and the trial results of different judgments in the same case appeared. Through the statistics of recent cases of common wills published by the China Judgements Online and analysis two representative cases, this paper summarizes the necessity and feasibility of establishing a common will system in China and carried out a more detailed analysis on the effect of the husband and wife's common will, identification of the effective time and the change and withdrawal of the common will. The following provisions are important mattes that must be considered when constructing a common will system: Conditionally affirming the effect of the common will by limiting the scope of the subject and property of the common will; The effect of the division of the estate occurs only after the death of both parties to the common will; Under the premise that there is no agreement between the parties after the death of one party, the surviving party can only change and withdrawal the content of the will belonging to the personal property, etc.