 He traced his ancestry to Yangshi (), an aristocrat of the Jin state in the Spring and Autumn period.As Yangshi's estate was located in an area called "Bu" (步; around present-day Linfen County, Shanxi), his descendants adopted "Bu" as their family name.One of Yangshi's descendants was Bu Shusheng (步叔乘; or Bu Shucheng), a disciple of Confucius.