YU Qingsong (1897-1978), born in Xiamen, Fujian Province. In 1918, he began his study of architecture in USA, taking up astronomy later, and received his Ph.D. degree in the University of California in 1926. He succeeded Gao Lu as the director of Astronomical Institute of the former Academia Sinica, and was deputed to the establishment of the Purple Mountain Observatory from 1929 to 1941. He was engaged in the stellar physics.