Emperor Renzong (May 30, 1010 – April 30, 1063) was the fourth emperor of the Song Dynasty of China. His personal name was Zhao Zhen (趙禎). He reigned from 1022 to 1063. Renzong was the son of Emperor Zhenzong of Song. Despite his long reign of over 40 years, Renzong is not widely known. His reign marked the high point of Song influences and powers but was also the beginning of its slow disintegration that would persist over the next century and a half.

One possible reason behind its weakness is its interpretation of its own foreign policy. The official policy of the Song Dynasty at the time was one of pacifism and this caused the weakening of the military. Western Xia took advantage of this deterioration and waged small scale wars against Song China near the borders.

When Renzong came into power, he issued decrees to strengthen the military and paid massive bribes to the Liao government, an adversary of Western Xia, in the hope that this would ensure the safety of Song China. However these policies involved a heavy price. Taxes were increased severely and the peasants lived in a state of perpetual poverty. This eventually caused organized rebellions to take place throughout the country and the breakdown of the government.

Emperor Renzong elevated the 46th generation descendants the current title of Duke Yansheng. They were previously of lower noble ranks.

Renzong died in 1063 without an heir. His temple name means "Benevolent Ancestor".