Effect The effect of sintering additives ($SiO_2$, $Al_2O_3$, Clay) on the mechanical characteristics of sintered zircon was investigated. 1 vol% of additives in zircon powder was was sintered at $120{sim}1500^{circ}C$, the mechanical characteristics were measured, and microstructure analysis were was conducted. $Al_2O_3$ and clay additions increase the formation of monoclinic and tetragonal-$ZrO_2$ formation. An addition of SiO2 addition suppressed the formation of tetragonal-$ZrO_2$ formation., The A specimen sintered at $1400^{circ}C$ showed the a density of $4.05;g/cm^3$ and the a microhardness of 1120 HV, respectively.