Early life and education
Rong was born on 27 August 1930 in Guangzhou, Guangdong, Republic of China, with his ancestral home in Nanping, Zhuhai. His father was in the military, and the family became refugees during the Second Sino-Japanese War. He was frequently on the run with his mother and siblings to evade Japanese occupation.
After the surrender of Japan in 1945, Rong returned to Guangzhou and resumed his education. In September 1949, he entered the Civil Engineering Department of Lingnan University (Guangzhou). In 1952, when the Communist government reorganized China's higher education according to the Soviet model, Lingnan's engineering departments became part of the newly established South China Institute of Technology (now South China University of Technology), and Rong was a member of the first class that graduated from the university in July 1953.