Boron carbide (B4C) powder has been prepared by carbothermal process using boric acid and citric acid as raw materials. Aqueous solution of boric acid in presence of citric acid forms a stable gel under controlled pH condition.The gel on subsequent pyrolysis under vacuum yields a precursor powder consisting of boron oxide and carbon. The precursor is heated under vacuum at 50°C/h up to 1450°C and the product obtained has been characterized by X-ray diffraction (XRD), chemical analysis, particle size analysis and scanning electron microscopy. XRD pattern shows that the product consists of B4C and carbon (graphite). Presence of free carbon (11.1 wt%) indicates boron loss in the carbothermal reaction. Boron loss has been calculated to be 11.3 wt%. Boron carbide powder obtained is composed of near equiaxial particles of narrow size distribution having a median size of 2.25lm.