$alpha$-SiC(B; 0.4 wt, C; 3 wt%) was sintered in Ar atmosphere from 205$0^{circ}C$ to 220$0^{circ}C$ by means of pressureless sintering and gas pressure sintering in order to find optimum sintering condition of $alpha$-SiC. Mechanical properties and microstructures of sintered bodies were investigated according to sintering method. The effect of sintering condition on sinterability of $alpha$-SiC was also examined by using the dilatometer. 97.5% and 98.8% of theoretical density were obtained from pressureless sintering and gas pressure sintering of $alpha$-SiC powder, respectively. And modulus of rupture was measured as 270~350 MPa and 420 MPa respectively.