The disclosure provides a pharmaceutical composition for retarding liver cancer growth, improving liver function, liver fibrosis, liver cirrhosis and liver inflammation, and promoting damaged liver regeneration, including: a proanthocyanidin with an effective amount; and a pharmaceutically acceptable carrier or salt, wherein the monomer units of the proanthocyanidin have the following formula. In the formula, when R 1 is OCH 3 , R 2 is OH and R 3 is H, when R 1 is OH, R 2 is H and R 3 is H, when R 1 is OH, R 2 is OH and R 3 is H, or when R 1 is OH, R 2 is OH and R 3 is OH, and R 4 is 3-(±)-OH, 3-(²)-OH, 3-(±)-O-sugar or 3-(²)-O-sugar.