Zhongshan is a famous hometown to many overseas Chinese. Overseas Chinese from Zhongshan living abroad are concerned about the urban development of their hometown and have offered tremendous financing resources. They have returned to their hometown and participated in government, invested in municipal development, improved public services, established industry and donated to schools. These efforts not only led to Zhongshan’s business economy boom, but also effectively promoted the urban construction process of modern Zhongshan. This paper traces the urban construction in Zhongshan during the period of the Republic of China, and investigated the great contributions of overseas Chinese to the urban development of modern Zhongshan.