At the age of 12, Hou became the youngest player ever to participate in the Women's World Championship (Yekaterinburg 2006) and the Chess Olympiad (Torino 2006). In June 2007, she became the youngest Chinese Women's Champion ever. She achieved the titles of Woman FIDE Master in January 2004, Woman Grandmaster in January 2007, and Grandmaster in August 2008. In 2010, she won the 2010 Women's World Championship in Hatay, Turkey at age 16. She won the next three championships in which the title was decided by a match (in 2011, 2013 and 2016, with a total of ten wins to zero losses and 14 draws against three different opponents), but was either eliminated early or declined to participate in the championships in which the title was decided by a knockout tournament (in 2012, 2015 and 2017).