$eta$-Sialon has been regarded as one of promising materials showing high strength, fracture toughness, corrosion resistence and wear resistence. The improvement of the fracture toughness and tribological properties of $eta$-Sialon (Z=1) has been attempeted by fabricating the $eta$-Sialon/ SiC whisker composite. Each of green body composed of following ingredients, i.e., Si3N4, AlN, Y2O3 nd SiC, respectively, was first fired at 178$0^{circ}C$ for 3hrs in N2 atmosphere and then post-HIPed at 173$0^{circ}C$ for 1 hr under 170 MPa for N2 gas pressure. The fracture toughness, flexural strength and tribological properties increased with increasing SiC whisker content, despite the reduction of the relative density and hardness. $eta$-Sialon/15 vol% SiC whisker showed a significant enhancement of wear resistance compared to the monolithic $eta$-Sialon. The addition of SiC whisker caused the reduction of the density and hardness, but induced the increment of wear resistance.