We report a carbothermal reduction process for massive synthesis of monolithic W_18O_49 phase from tungsten oxide in the presence of carbon source. Carbon black powder was used as a carbon source and added to WO_3 by 40 weight percent. Bundles of W_18O_49 rods were formed over the temperature range of 800°C°C to 900°C. Pure W_18O_49 bundles could be separated from the mixture of W_18O_49 and residual carbon black powder. Field emission character of W_18O_49 phase was determined using the extracted W_18O_49 rods. Flat lamp fabricated from the W_18O_49 rods showed the turn-on field of 9.3 V/µm.