ZrB 2 and ZrB 2 -SiC powders have been produced by reducing ZrO 2 and ZrSiO 4 with B 4 C without using any furnace. Magnesium was added to the mixtures of (ZrO 2 +B 4 C) and (ZrSiO 4 +B 4 C). The reaction has been assisted by a floral thermite packed around the compacts. By introducing elemental Si into (ZrO 2 +B 4 C) mixture, composite powders of ZrB 2 -SiC formed. After leaching out MgO with suitable HCl water solution, the product was analysed by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The effect of Si, B 4 C, and Mg on the extent of formation of ZrB 2 , ZrB 2 -SiC, and other phases has been studied. Formation of nano-sized ZrB 2 and ZrB 2 -SiC composite powders was identified. The adaptability of the process for bulk production was examined.