According to legend, when Yao Di, the ancestor of Xu, was a saint and later generations took Xu as their surname. Another is Sun Boyi, the descendant of Emperor Yan, who assisted Emperor Yao as the official and put him in charge of the four mountains. In the world, the descendants of Sishan were first named Xu (now Xuchang, Henan), so their descendants took Xu as their surname. At the beginning of the Warring States Period, the State of Xu was destroyed by the State of Chu, and descendants were scattered all over the country, still taking the State as their surname. There are six branches of Xu surname in China: Levin Xu, Anlu Xu, Ruyang Xu, Taiyuan Xu, Jinling Xu and Zhongshan Xu, all of which originated in Xuchang, Henan.

The earliest ancestor of Fujian, the Xu family, has the word Ying. Posthumous title Wu Jingtang was born in Xuzhou, Henan. In the fourth year of the Eastern Han Dynasty (79), Zhang Jian was appointed as General Zuo Ling, who became the capital of Xu, unified the troops to quell the chaos and stationed in Tong 'an. His descendants lived in Tongan, the former site was Yingcheng, which is now Yingcheng Lane, Xiaoximen, Tongan County. Tongan City was founded in the 15th year of Shaoxing, Song Dynasty (1 164), which was more than 1000 years later than Xudu City. In the fourth year of Tiancheng in the late Tang Dynasty (929), King Min promoted Datong to Tongan County, so there was no Tongan in history. Xu Du is the ancestor of Xu who entered Fujian, and his 15 sons live in all parts of Fujian. In Tang Xizong, in the second year of Guangming (88 1), the Huang Chao uprising led to a great change in Tongan, and the two sons of Yong Gong moved to Tongan again until the Song Tongan Xu Shixing. However, according to research, there are not many Tongan Xu Shi sent by Xu Du, and they may later live in other counties, Jinmen and Taiwan Province Province, or in northern Fujian.

In addition to the above-mentioned many capitals, there are two Xu surnames entering Fujian. One is He Tianzheng, who entered Fujian with him in the first year of the Tang Dynasty (669). This branch, called the Xu family in Runan, mainly flourished between Zhangzhou and Chaoshan. The genealogy records in the Tang and Song Dynasties are relatively clear, and the lineages in different places are basically the same, and there is no record of leaving Jinjiang. However, during the anti-yuan period, the losses were heavy. There is only one Naijing in Zhaoan, and there are few other counties in Zhangzhou. Later, people who went south from Quanzhou Xu inherited the Tianzhenggong system, and because Quanzhou Xu claimed to be a Zhangzhou native and a descendant of Tianzhenggong in order to avoid the harm of Pu Shougeng after the Yuan Dynasty, the branch was closely related to Jinjiang Xu. Fujian Xu regarded Xu Tao as the ancestor of Zhang Nan and Xu Naijing as the ancestor of Zhao 'an revival.

Second, in the second year of Tang Jinglong (708), he served as Wu Rong's secretariat of Xu Fugan. This branch belongs to Xu Shi and Levin, assisted by Li Yuan's great-grandfather Xu Shao, who was tall when he was young. It is recorded in various historical books. Li Yuan named Xu Shao as the Duke of Anlu County, especially after three generations. Therefore, this branch is also called Anlu Xu, but it is actually from Xuzhou, Henan. In Tang Zhongzong, Wei Hou's mother and daughter competed with Shangguan Waner to sell titles, and Xu Fugan changed from the secretariat of Zhongzhou, a heavy county, to the secretariat of Wurongzhou, a remote county. She was poor and ill and died in May. Her sons Mao Wen and Mao Wu were buried in Huguang Mountain in Putian, and now she lives in Dongqiao Xu in the south of the mountain. Mao Wenju lives in Yonghe JOE Lane and Xuzhai Lane in Maowu East and West. The first part of Maowu began in the Kaiyuan period of the Tang Dynasty, based on Dongshi, and spread overseas. During the Tang and Song Dynasties, Quanzhou was a maritime merchant family, and also set foot in officials. Shang Gang, the son of a scholar in Yuan Dynasty, learned that all 23 members of his family died in the Juan Rebellion when he was building Anfu. Only his 12-year-old son Ji Xu was rescued by Shaanxi officials and returned to Dong Shiyi's uncle Xu Shiyi. After Ji Xu became famous, the emperor gave him a mountain to study and called it "grace". The world calls this auxiliary system Ji Xu system.

On the other hand, Quanzhou has a school called "Shu Zhen" Xu, who is a famous minister of science and a descendant of Xu Heng, a teacher of the country. Xu Heng's fourth son learned from Xuan, and obtained the mission of Fujian Minhai Dao Chinese medicine to Fujian Manchu and Qing Dynasties. During the Liu Futong Uprising, he lived in Tang Hong Township outside the West Gate of Fuzhou. Since Xuanzi's second son, Shang Lian, went to Nanjun Lane, Quanzhou, and lived in Baishan, East Normal University, the fourth son's Wen Zhai was separated from Lu Cuo, formerly known as Pincuo, and the local name was Sancha, hence the name Wen Zhai. Xu Shi in Dabai Mountain became a duet in Guangxu period of Qing Dynasty. In addition, Xu Xu Village was built and later merged into Xuxikeng Four Rooms.