A carbon-based metal composite material comprising a carbonaceous matrix and a metal component dispersed therein, wherein 90 volume % or more of pores present in the carbonaceous matrix are replaced by the metal component and the content of the metal component is 35 % or less based on the total volume of the carbon-based metal composite material; a method for preparing a carbon-based metal composite material by the impregnation of a formed article of carbon with a molten metal under pressure which comprises preheating the formed article of carbon and then forcing the molten metal into pores of the formed article of carbon by the application of a pressure of 200 kg/cm or more, to thereby impregnate the formed article with the molten metal; and a formed article in the shape of a substrate for electronic equipment which comprises the carbon-based metal composite material.