InN nanowires were prepared on Si substrates by low pressure chemical vapor deposition using Au as the catalyst. Scanning electron microscopy showed that the diameter of these nanowires is 60—100 nm, and the length is larger than 1 μm. High resolution transmission electron microscopy showed that the synthesized nanowires are a mixture of hexagonal and cubic phase. The field electron emission characteristics of these InN nanowires are good and the field emission current is stable. The turn-on electric field was 10.02 V/μm(the current density being 10 μA/cm2)，and at the high electric field of 24　V/μm，the current density was as high as to 5.5 mA/cm2. The field electron emission mechanism of these nanowires is discussed.