Xu Chengyu
{{family name hatnote|Xu|lang=Chinese}}
{{Infobox officeholder
| honorific_prefix =
| honorific-suffix =
|name= Xu Chengyu
{{nobold|徐承煜}}
|image=
| office = Senior Deputy Minister of Justice
| term_start = 16 November 1898
| term_end = 13 February 1901
| alongside = Akdan (until 1899), Puting (1899), Chongxun (since 1899)
| predecessor = Li Peiyuan
| successor = Xue Yunsheng
| office1 = Senior Deputy Minister of Rites
| term_start1 = 30 July
| term_end1 = 12 November 1900 (acting)
| alongside1 = Ronghui
| predecessor1 = Zhang Baixi
| successor1 = Li Fuzao
| term_start2 = 9 October
| term_end2 = 16 November 1898 (acting)
| alongside2 = Kuoputongwu
| predecessor2 = Wang Xifan (acting)
| successor2 = Ge Baohua (acting)
| office3 = Minister of Court of Imperial Sacrifices
| term_start3 = 15 September 1896
| term_end3 = 1897
| alongside3 = Qingfu
| predecessor3 = Kung Chao-Yuan
| successor3 = Chen Bangrui
| office4 = Minister of Court of the Imperial Stud
| term_start4 = 10 January
| term_end4 = 15 September 1896
| alongside4 = Song'an
| predecessor4 = Yang Yü
| successor4 = Liu Enpu
| occupation = politician
| father = Xu Tong
| relations =
| children =
| education = Imperial Academy
| birth_date = 1838
| birth_place =
| death_date = {{death date and age|1901|2|26|1838|||df=yes}}
| death_place = Caishikou Execution Grounds, Beijing, Qing Empire
| blank1 = Courtesy name
| data1 = Nanshi (楠士)
| allegiance = Qing dynasty
| branch = Han Chinese Plain Blue Banner
| serviceyears =
| rank =
| commands =
| battles = Boxer Rebellion
| laterwork =
}}
Xu Chengyu ({{zh|c=徐承煜}}, 1838–1901), courtesy name Nanshi (楠士), was a Qing dynasty official from the Han Chinese Plain Blue Banner. He was a son of Xu Tong.
Xu Chengyu obtained the xiucai (秀才) degree in the imperial examination and was selected a gongsheng (貢生) of the Imperial Academy in 1861. He had served as director of the Ministry of Revenue Shaanxi Bureau (戶部陝西司郎中), staff of Huiling Mausoleum construction office (惠陵工程處隨同辦事), Minister of the Court of the Imperial Stud (太僕寺卿), Assistant Commissioner of Transmission (通政使司參議), associate director of the Court of the Imperial Clan (宗人府府丞) and other positions.{{cite web | url = https://cbdb.fas.harvard.edu/cbdbapi/person.php?id=0063270 | title = Xu Chengyu }} He was promoted to the Senior Deputy Minister of Justice (刑部左侍郎) in 1898.{{cite web | url = https://newarchive.ihp.sinica.edu.tw/sncaccgi/sncacFtp?ACTION=TQ,sncacFtpqf,SN=006655,2nd,search_simple |title = 徐承煜 }}
Like his father, Xu Chengyu stood in the way of Hundred Days' Reform. Although he was hostile to Western culture, he was quite accepting of Western things in terms of material life enjoyment. It was said that he bought Western-style furniture and smoked cigars, for which he was scolded by his father. During the Boxer Rebellion, Xu Chengyu supported to use the Boxers to fight against Western countries. He was appointed the execution witness (監斬官) of Xu Yongyi, Lishan, Xu Jingcheng, Lianyuan and Yuan Chang.{{wikisource-inline|zh:夢蕉亭雜記|夢蕉亭雜記}} When Beijing fell to the Eight-Nation Alliance in 1900, Xu Chengyu persuaded his father to commit suicide with him. However, after Xu Tong committed suicide, he regretted it. He buried his father's body in the backyard and tried to fled from the capital{{cite web | url = https://epaper.gmw.cn/zhdsb/html/2013-09/18/nw.D110000zhdsb_20130918_4-04.htm |title = 徐桐父子}} however, was captured by Japanese soldiers. In the next year, the victorious Eight-Nation Alliance named him as one of the masterminds behind the rebellion and demanded that he be executed.{{wikisource-inline|United States Treaty Series/Volume 1/Boxer Protocol|Peace Agreement between the Great Powers and China.}} Zhang Zhidong suggested to the Empress Dowager Cixi that Xu Chengyu should be returned to the Qing court for trial, and then force him commit suicide.{{cite book | url = https://books.google.com/books?id=dTMSEAAAQBAJ&dq=%E5%BE%90%E6%89%BF%E7%85%9C&pg=RA1-PA53 | title = 張之洞的外交政策 |author= 李國祁 |year = 1984 | publisher = 中央硏究院近代史硏究所 | page = 254}} Xu Chengyu was dismissed from all official positions and later, executed at the Caishikou Execution Grounds together with Qixiu on 26 February 1901.{{cite web | url = https://worldjpn.net/documents/texts/pw/19010907.T1J.html | title = 北淸事變に関する最終議定書（北清事変に関する最終議定書，北京議定書） |language=ja}}{{cite web | url = https://db.history.go.kr/item/compareViewer.do?levelId=jh_017_0040_0230 | title = 諭 宣言刑量 承諾公書 淸國全權委員에게 送達 件 |language=}} Xu Chengyu was so frightened that he fainted and fell unconscious during the execution. Unlike him, Qixiu accepted the fate very calmly.{{wikisource-inline|zh:清史稿/卷465#徐桐|清史稿/卷465}} (Draft History of Qing Volume 465)