Abstract: This study is the carbon nanotube films（CNT）in the Preparation and Field Emission Effect.The carbon nanotubefilms were fabricated in 500℃ temperature by microwave plasma chemical vapor deposition（MPCVD） method.The glass with a Ti mental layer was used as substrate.Before fabricating,the substrate was polling by the SiO₂ with Fe.The CNT films were evaluated by Raman scattering spectroscopy,scanning electron microscopy（SEM） and Transmission electron microscope（TEM）.The field emission properties were tested by using a diode structure in a vacuum.A phosphor-coated indium tin oxide（ITO） anode was used for observing and characterizing the field emission.It was found that CNT films exhibited good electron emission properties.The turn-on field was only 1.1V/μm and the emission current density as high as 9.0mA/cm² was obtained under an applied field of 3.0V/μm for the last operation.The growth mechanism and field emission properties of the CNT films are discussed relating to microstructure and electrical conductivity.