This work studies the fabrication and pressureless sintering of silicon carbide (SiC) refractories. SiC particles were adopted as aggregates, introducing different amounts (20%, 30%, 40%, 50%, and 60%, by mass) of submicron SiC powder, adding resin as the binder and the carbon source, and B4C as the sintering aid. It is found that when the mass ratio of B4C to the submicron SiC powder is 3%, the optimal sintering can be obtained. With the increase of the submicron powder addition, the sintering linear shrinkage increases and the mechanical properties enhance. The optimal sintering temperature is 2 050-2 100 ℃.