We fabricated FEDs(Filed emission devices) based on ZnO nanowires. The ZnO nanowires were synthesized on Au thin films by hydrothermal method at the temperature of 90[$^{circ}C$] on hot plate. In order to form tips of the ZnO nanowire, SDS(Sodium Dodecyl Sulfate) was mixed in O.05-0.3[wt%] solution as capping material. After 2 hour growth, we obtained nanowires of chain form The high-purity nanowires showed sharp tip geometry with a wurtzite structure. The field emission properties of the ZnO nanowires were investigated in high vacuum chamber. The turn-on field for the ZnO nanowires was found to be about 4.1[V/${mu}m$] at a current density of 0.1[${mu}A/cm^2$].