The present invention provides a method for the normalized culturing of corneal endothelial cells. More specifically, the present invention provides a culture-normalizing-agent of a corneal endothelial cell, comprising a fibrosis inhibitor. In detail, the present invention provides a culture-normalizing agent comprising a transforming growth factor (TGF) β signal inhibitor. The present invention also provides a culture medium for culturing a corneal endothelial cell normally, which comprises the culture-normalizing agent according to the present invention and corneal endothelium culture components. The present invention also provides a method for culturing a corneal endothelial cell normally, comprising the step of culturing a corneal endothelial cell using the culture-normalizing agent according to the present invention or the culture medium according to the present invention.
