 Cheng was the second child of a poor barrel and cask maker, born near the prosperous mid-Yangtze valley city of Wuchang, Hubei.His father had briefly attended a mission school and joined the Congregational church When Cheng was six years old, his father and uncle opened a lumberyard which was successful enough that Cheng was able to attend a primary school run by charity.He still often had to leave school to help in the family business.