We report a carbothermal reduction process for massive synthesis of monolithic WO phase from tungsten oxide in the presence of carbon source. Carbon black powder was used as a carbon source and added to WO by 40 weight percent. Bundles of WO rods were formed over the temperature range of 80 to 90. Pure WO bundles could be separated from the mixture of WO and residual carbon black powder. Field emission character of WO phase was determined using the extracted WO rods. Flat lamp fabricated from the WO rods showed the turn-on field of 9.3 V/