A posthumous name is an honorary name given mainly to revered dead people in East Asian culture. It is predominantly used in Asian countries such as China, Korea, Vietnam, Japan, Malaysia and Thailand. Reflecting on the person's accomplishments or reputation, the title is assigned after death and essentially replaces the name used during life. Although most posthumous names are given to royalty, some posthumous names are given to honor significant people without hereditary titles, such as courtiers or military generals.

To create a posthumous name, one or more adjectives are inserted before the deceased's title. The name of the state or domain of the owner may be added to avoid ambiguity.

Early mythological rulers such as Emperor Yao were known to have posthumous names. Archaeological discoveries have shown that the titles of kings as far back as the Zhou dynasty (c. 1046 to 256 BC) are posthumous names, as in the cases of King Wu and King Wen. Posthumous names commonly made tracing linear genealogies simpler and kept a bloodline apparent.

In the Zhou dynasty, the posthumous name was usually only one character, such as Wen ('cultured') or Wu ('martial'). Over time, rulers began adding more characters to their ancestors' posthumous names. By the time of the first emperor of Tang, the length had grown to seven characters, which was taxing to pronounce or write. Therefore, emperors after the Tang dynasty are commonly referred to by either their temple name (Tang through Yuan dynasties) or era name (Ming and Qing dynasties), both of which are always two characters long.

The use of posthumous names temporarily stopped when emperor Qin Shi Huang of the Qin dynasty proclaimed it disrespectful for the descendants of emperors to judge their elders by assigning them descriptive titles. The Han dynasty resumed using posthumous names after the fall of the Qin.

Posthumous names were used by non-Han rulers of the Sixteen Kingdoms, Nanzhao, Liao dynasty, Western Xia, Jin dynasty, Yuan dynasty, Qing dynasty, Silla, Japan, and Vietnam. King names of Hồng Bàng dynasty and Mahan followed the posthumous naming but are considered later works. Some rulers, such as Wu Zetian or rebel leaders, had similarly styled regnal names when they were alive.

Most monarchs inherited the throne and did not give negative posthumous names to the previous monarch. Later monarchs lengthened or changed some names. Emperor Aizong of Jin and the Chongzhen Emperor were referred to by different names by different people. Qin Hui of the Song dynasty had a name with a positive connotation, was then given a negative one, and later had the positive name restored. After the Song dynasty, few received negative names. In Korea, the disfavored monarchs of the Joseon dynasty did not receive posthumous names.

Posthumous names can be praises (褒字) or deprecations (貶字). There are more praises than deprecations, so posthumous names are also commonly called respectful names (尊號; zūnhào) in Chinese. Sima Qian's Records of the Grand Historian extensively outlines the rules behind choosing the names. Most qualifications for a given name are subjective, repetitive, and highly stereotypical, meaning posthumous names are often chosen arbitrarily. Court historians usually provide such names according to the deceased's notable deeds.