Guo Jia (170–207),courtesy name Fengxiao, was an advisor to the warlord Cao Cao in the late Eastern Han dynasty. Throughout his 11 years of service, Guo Jia aided Cao Cao greatly with his brilliance and foresight, and his strategies were instrumental to Cao's triumphs over rival warlords such as Lü Bu and Yuan Shao. For example, four years before Cao Cao's decisive victory over Yuan Shao at the Battle of Guandu, Guo Jia had already foreseen that Cao would win when he pointed out ten advantages Cao had over Yuan.
The authoritative historical source on Guo Jia's life is the Records of the Three Kingdoms (Sanguozhi), which was written by Chen Shou in the third century. In the fifth century, Pei Songzhi annotated the Sanguozhi by incorporating information from other sources to Chen Shou's original work and adding his personal commentary. Some alternative texts used in the annotations to Guo Jia's biography include: Fu Zi, by Fu Xuan; Wei Shu (Book of Wei), by Wang Shen, Xun Yi and Ruan Ji; Shiyu (Accounts of this Generation), by Guo Song.
Guo Jia (born 1980-09-24 in Xiangtan, Hunan) is a female Chinese softball player who competed at the 2004 Summer Olympics. In the 2004 Olympic softball competition she finished fourth with the Chinese team. She has competed for Team China at the 2008 Summer Olympics in Beijing.