The real Xu family tree appeared after Wei and Jin Dynasties. The genealogy of Xu surname was written by Jia Bizhi in the Eastern Jin Dynasty and compiled by officials in the Southern Dynasties, such as Hundred Genealogies, Eighteen Genealogies and Newly Collected Genealogy. In the Tang Dynasty, Emperor Taizong ordered Gao Shilian to compile Genealogy, and the Xu family was classified as the best. In the Southern Song Dynasty, Chen said in Xu's Genealogy: "Emperor Taizong passed down from generation to generation, played the genealogy of the world, retired from the new door to the old one, and was poor on the left. His surname was 193+089 1, and Xu was also the first." Since then, a series of official genealogies about Xu, such as Eight Years of Zhenguan, Records of Surnames, Records of Surnames, Genealogy of Wang Family in Xinji Tianxia, Compilation of Yuanhe Surnames, etc., have preserved some genealogical data of Xu in the Tang Dynasty. In Wei, Jin, Sui and Tang Dynasties, apart from official genealogy, private genealogy was also very popular. During this period, people surnamed Xu also compiled many genealogies privately, and the genealogy of the giant officials of the State Genealogy Bureau was compiled from these vast private genealogies. After the elimination of the peasant uprising at the end of the Tang Dynasty and the scuffle of feudal separatist forces, most of the genealogy before the Tang Dynasty was lost, and genealogy, as a science, was rarely circulated, which is called "the best genealogy" in history books. Genealogy reached its peak in the Qing Dynasty and became an important part of clan activities in the Qing Dynasty. This trend continued until the Republic of China, so that most of the existing genealogies, including Xu's, were compiled in the Qing Dynasty and the Republic of China.

As the most popular surname in China, Xu attaches great importance to the compilation of genealogy and is one of the surnames with the most genealogy. According to the statistics of several major genealogy collections in China, there are 2,770 kinds of genealogy in Beijing Library, among which 87 kinds are Xu's genealogy, ranking third after Yong (1 19) and Chen (1 10). There are 2,594 kinds of China genealogy in Utah genealogy society, among which 67 kinds are Xu, ranking sixth. The Genealogy Research Center of Shanxi Academy of Social Sciences has 2565 kinds of genealogy, of which 63 are Xu, ranking eighth. It is the most prosperous period of genealogy compilation, and most of the existing genealogies in China come from this period, which is rich in content and complete in style, which is beyond the reach of other generations. The Xu family tree in Wucheng, Jiangyin in this period is a model of traditional family tree in China. This score was first compiled in the Xuanzong Xuande period of the Ming Dynasty (1429), and was compiled five times in the Ming Dynasty alone. In the Qing Dynasty, Xu Jiachuan and Xu Dong maintained Xin Chou Pu, revised Daoguang Xu Bing Pu, Xu Tongzhi Gui You Pu, and Xu Guangxu Ding Wei Pu. In particular, the compilation level of Tongzhi Gui You Spectrum is the highest, so that "Zhao Muxu makes the world auspicious, and the test is full of documents". Therefore, Wu Cheng's genealogy is known as "the crown of genealogy in the north and south of the Yangtze River".

The existing genealogy of Wu was rebuilt by Xu Renxin, the tribal leader of Wuma Town during the Anti-Japanese War. This reconstruction is based on Guangxu genealogy, and the main contents of reconstructing Wu genealogy many times in Ming and Qing Dynasties are preserved. This spectrum consists of 52 volumes and 59 volumes. Xu Xiake, an outstanding traveler and geographer in Ming Dynasty, was originally from the Xu family in Jiangyin. Thanks to the preservation of the Xu family tree in Wucheng, Jiangyin, people have a deeper understanding of Xu Xiake himself and his predecessors and descendants with a history of official loss. According to genealogical records, the Xu family in Wucheng, Jiangyin is a descendant of Xu Zhi in the late Eastern Han Dynasty. Xu Zhi is a native of Nanchang County, Jiangxi Province, and is called "a scholar in Nanzhou". Xu Gu, the ancestor, was appointed as Kaifeng Yin at the end of the Northern Song Dynasty. Jinbing invaded south and Songshi crossed south, bringing a large number of "Central Plains documents" and moving to Hangzhou with the small court in the Southern Song Dynasty. Xu Shoucheng, the fourth ancestor of the Southern Song Dynasty, was appointed as Taiwei of Wujun in the first year of Ning Zongqing, and his family moved to Suzhou. Since then, "the surnames of various schools are scattered in Hou Jing, Yun Jian and Qinchuan", namely Yixing, Songjiang and Changshu. In the Yuan Dynasty, Xu Ganxi, the son of Xu Shoucheng, moved to live in the Wulin in Xishunling, Jiangyin County, so the fifth ancestor Xu Ganxi was actually the ancestor of the Xu family in Jiangyin Wulin. The specific landscape of Wucheng is in the mansion of Zhutang Township, Jiangyin County today. Xu Lin, the ninth ancestor, once wrote to the Ming court with a cloth coat and sent messengers to Xishu to appease the Qiang people. After resigning from his post, he returned to his hometown, widely bought land, and became a wealthy family and a huge literature room with nearly 100 thousand mu of land and thousands of books. From Xu Yi, the eleventh ancestor, to Xu, Xu Qia IV, there are literary names. When Xu Youmian, the father of the sixteenth ancestor Xu Xiake, arrived, although the family wealth had fallen, the husband and wife made efforts to "revive the family wealth".

After the genealogy is compiled, it must be updated within a certain period of time to ensure a complete record of the continuation of the family bloodline. As for how often the genealogy should be updated, there is basically no uniform regulation and it is in a spontaneous state. For example, jade records in Qing Dynasty are revised once every 10 year, and folk genealogies are revised once every 10 year, 15 year, 30 year and 60 year, with a maximum of three generations, that is, once every 90 years. However, although each family has its own regulations, due to external reasons such as war, war, plague and natural disasters, as well as internal reasons such as the family's own migration, talents, funds, materials, and understanding of the role of genealogy, few families continue to repair in strict accordance with relevant regulations, at most for a certain period of time.

In the existing genealogy of Xu, the earliest record of genealogy revision can be found in Sui Dynasty.

According to Xin 'an Xu's Genealogy, there are memorials given to the emperor by university students in Gao Shilian during the 13th year of the Great Cause (6 17). As mentioned in the memorial, in order to compile the genealogy, Emperor Yang Di wrote a letter to the Ancient Genealogy of Kyushu. The genealogy here is a simple form of genealogy, which only talks about lineage, but it can also be seen that Xu was compiled by the Sui Dynasty. In addition, in the first year of Emperor Wu Zetian's longevity in the Tang Dynasty (696), Wu Zetian wanted to compile another genealogy, and wrote, "As a courtier, he belongs to a famous family in the four seas, so that his courtiers can take their names and compile them into genealogies for future generations. "That is, officials were ordered to submit genealogy, and the imperial history in the temple and the assistant minister Xu in Zuo Buque obeyed the order and" entered the genealogy of famous ministers in previous dynasties ". The "genealogy" here is a little more detailed than the "genealogy" of previous lives. According to the records of the Xu family tree in Yanshou, the Xu family tree was revised as early as the second year of Guanghua (899).

Among the existing Xu genealogy, the twelve volumes of Xiao Liu Xu Genealogy have been revised eleven times in a row. This genealogy, also called Xiao Liu Xu Jiu Xiu's genealogy, was held in Ming Yingzong for ten years (1445) and in Qin Long, Mu Zong for four years (1570). Seventeen years of Kangxi (1678), two years of emperor sejong's Yongzheng (1724), thirty-two years of emperor gaozong's Qianlong (1767), eleven years of Daoguang in Xuanzong (183 1) and nine years of Xianfeng in Wenzong. From the Wanli period of the Ming Dynasty to the five years of the Republic of China, Qiao Xu's genealogy has also undergone ten revisions. Coupled with the old sequence of the Song Dynasty, it can be seen that there are more than ten revisions. The most frequently revised genealogy is Yunyang Xu's genealogy, which was revised 13 times from the 11th year of Wanli (1583) to1926,343. The intervals for each modification are: 15, 30, 34, 40, 35 and 466 respectively. This frequency and the frequency of spectrum trimming are rare in other families.

According to Comprehensive Catalogue of Genealogy in China, Summary of Genealogy Collected in Shanghai Library and China Genealogy Catalogue of Shanxi Academy of Social Sciences, there are 789 kinds of genealogies of Xu, and only Shanghai Library has collected 326 kinds. But this is only found in these three catalogues. There will never be less than 1,000 kinds of public and private collections that are not in these three catalogues, and the exact number can only be obtained after the China genealogy catalogue is completed.