Born in Huai Ning, Anhui Province, Xiao Sun studied under Jiang Yun (1847-1919) following the style of the early Qing Dynasty painter Wang Hui (1632-1717), giving him a solid traditional foundation. He thus came to be strongly influenced by the Tao-Chi branch of the Huang Shan School, which focused on emphasizing the dramatic aspects of Mt. Huang. Later moving to Beijing he played a major role in introducing this painting style, which later came to be known as the Anhui School.
After the formation of the National Academy of Art in Beijing he was appointed professor of Chinese Painting and held this position until the outbreak of the Sino-Japanese war