The present invention provides a method for effectively exerting a cell proliferation promoting effect of a purine nucleic acid-related substance. The present invention provides a composition for cell proliferation containing a purine nucleic acid-related substance and a pyrimidine nucleic acid-related substance. Further, the present invention provides a method for potentiating the cell proliferation promoting effect of the purine nucleic acid-related substance by using the purine nucleic acid-related substance in combination with the pyrimidine nucleic acid-related substance. Still further, the present invention provides a method for promoting cell proliferation, where the method comprising applying purine nucleic acid-related substance in combination with the pyrimidine nucleic acid-related substance to the skin or mucosa.
