Abstract: The invention provides a substrate suitable for cell culture observation and a method of observation using the same. Crystalline carbon such as a graphite powder is mixed into a thermosetting resin such as a furan resin, and the mixture is molded in the shape of a sheet and carbonized to produce a carbon substrate; then, a cell is made to adhere to the carbon substrate, and the cell is caused to proliferate on the carbon substrate and observed using a microscope.