A will refers to a legal act that a testator personally disposes of his or her estate or other affairs in the manner prescribed by law before his or her life, within the scope permitted by law, and takes effect when the testator dies.
 1、 A testator must have testamentary capacity. A will is a civil act, and the founder must have the corresponding capacity for civil conduct. According to the current law of our country, only people with full civil capacity can have the capacity to establish a will, that is, testamentary capacity. People without full civil capacity do not have testamentary capacity.
 2、 A will must be a testator's expression of true will. A will must be the true declaration of will by the testator to dispose of his property, because the true declaration of will is a necessary condition for the validity of civil acts.
 3、 A will may not revoke the right of inheritance of a successor who lacks the ability to work and has no source of income. The testament shall reserve the necessary share of the estate for heirs who lack the ability to work and have no source of income.
 4、 The property disposed of in the will shall be the testator's personal property. A will is a civil act for a testator to dispose of his personal property, so he can only dispose of his personal legal property.
 5、 A will must not violate or harm the public interest and social morality.
 In addition, there are five statutory ways to establish a will, each of which has different conditions.
 Legal basis:
 Article 22 of the Inheritance Law of the People's Republic of China
 Wills made by persons without or with limited capacity are invalid. A will must express the true will of the testator, and a will made under duress or deception shall be invalid. A forged will is void. If a will is tampered with, the tampered contents shall be invalid.
 Article 17 of the Inheritance Law of the People's Republic of China
 A notarial will shall be made by the testator through a notary office.
 A self written will shall be written and signed by the testator, and shall be marked with the following year, month and day.
 A will written on behalf of the testator shall be witnessed by two or more witnesses, one of whom shall write on behalf of the testator, noting the next year, month and day, and shall be signed by the proxy, other witnesses and the testator.
 A will made in the form of a sound recording shall be witnessed by two or more witnesses.
 A testator may make an oral will in a critical situation. An oral will shall be witnessed by two or more witnesses. If a testator is able to make a will in writing or by recording after the emergency situation is relieved, his oral will shall be invalid.