The present invention provides a method for depositing self-aligned carbon nanomaterials (carbon nanoflake, carbon nanotube, carbon nanorod and carbon nanosphere), by inducing a gas chemistry for the carbon nanomaterials, on a substrate having a large area of several inches in diameter, under the conventional CVD diamond deposition conditions. The well-aligned carbon nanomaterials on the large area are applicable for sensitive base materials in the fields including biochemistry and electrochemistry.