The carbon complex film, Which consists of diamond grains, carbon nanotubes, amorphous carbon composition, were fabricated by microwave plasma chemical vapor deposition （MPCVD） method. The ceramic with a Ti mental layer was used as substrate. The carbon complex films were evaluated by Raman scattering spectroscopy, x-ray diffraction spectrum, scanning electron microscope. The field emission properties were tested by using a diode structure in a vacuum. A phosphor-coated indium tin oxide anode was used for observing and characterizing the field emission. The turn-on field was only 0.55V/μm and emission current density as high as 11mA/cm2 was obtained under an applied field of 2.18V/μm for the first operation. The growth mechanism and field emission properties of the carbon complex films are discussed relating to microstructure and electrical conductivity.