Chuang's parents were both table tennis players in Taiwan. His father was a national doubles champion, and his mother Li Kuei-Mei was a member of the national team. After the end of Li's career as a player, her son, Chih-Yuan, became one of her prodigies in table tennis. Chuang started competing in 1989, at the age of 8. From the age of 13 his mother sent him to China for training several times. Chuang first made it to the Taiwan national team in 1998. In 1999, Chuang made his World Championships and ITTF Pro Tour debut. At the end of 2000, his mother decided to let Chuang train in Europe, including France and Germany. The process made his matches a combination of the Chinese and European playing styles. 2002 was a sparkling year in Chuang's career. He reached his first three finals on the Pro Tour, but ended them all as the runner-up. He entered the world Top 10 listin September, won the silver medal at the Asian Games and participated in his first World Cup. At the year's end, he consecutively faced the opponents who defeated him in the previous three finals of the Pro Tour, and recorded three straight wins at the Pro Tour Grand Finals. He defeated Jean-Michel Saive in the quarter-final, Wang Hao in the semi-final, and Kalinikos Kreanga in the final, claiming the title of Grand Finals Champion. Chuang won his first Singles title on the Pro Tour at the Brazil Open in 2003, and reached No. 3, the highest world ranking of his career, at the end of the year. He advanced to the quarter-finals in the 2004 Athens Olympics, ending the Games with a loss to Wang Hao. In the men's doubles, he and teammate Chiang Peng-Lung reached the last 16, where they were beaten by Błaszczyk and Krzeszewski of Poland. In July 2008, his own table tennis stadium, Chih Yuan The Ping-Pong Stadium, opened in Kaohsiung, Taiwan. At that year's Olympics, he was beaten in the third round by Yang Zi of Singapore. As of June 2012 Chuang plays for Werder Bremen in the Bundesliga in Germany. He reached the bronze medal match at that year's Olympics, where he lost to Dimitrij Ovtcharov. In May 2013, in the 52nd World Table Tennis Championships held in Paris, France, Chuang Chih-yuan and Chen Chien-an defeated Hao Shuai and Ma Lin 9–11, 12–10, 11–6, 13–11, 9–11, 11–8 in the final, and won the Men's Doubles title. Chuang and Chen became the first athletes in Taiwan to win any World Table Tennis Championship title. On 2 September 2019 he announced not to play anymore for the Chinese Taipei national team. It was stated that the main reason for his decision was disagreement with the Chinese Taipei association in that he only wants to play for the Chinese Taipei in single competition.
