Abstract: The porous pyrolytic carbon was made by chemical vapor deposition in the temperature range from 1100~1550℃, using acetylene as the carbon source gas. Density of porous pyrolytic carbon was measured by image analysis technique. The microstructure of porous pyrolytic carbon was analyzed by SEM. The results show that: with the increasing of coating temperature at 1100~1250℃, the density of porous pyrolytic carbon increases; with the increasing of coating temperature at 1250~1350℃, the density of porous pyrolytic carbon reduces, and the density of porous pyrolytic carbon tends to be stable at＞1350℃ range; when the coating temperature equals to（1450±50）℃, the eligible porous pyrolytic carbon can be made.