Thermal shock fracture behaviors of SiC-whisker-reinforced alumina composites were investigated. Composites containing up to 60vol% SiC whisker were fabricated by SPS. Disc-on-Rod test was employed to characterize thermal shock fracture behavior. Futhermore,4-point bending tests with AE measurement were conducted. These experimental results showed that thermal shock fracture took place when thermal stress reached critical stress of maincrack formation and the value of the stress increased with whisker volume fraction in composites. SEM observations reveal the evidence of whisker bridging and few pullout, which suggests that the modification of interface properties will result in further toughening.