Thermal properties of the fault zone materials are of fundamental importance for estimate of frictional heat generation during earthquake. The properties across the Chelungpu fault zone activated by 1999 Chi-Chi earthquake, Taiwan, are measured using the drilled core penetrating the fault zone at around 1100 m depth. The fault zone contains four distinct fracture zones, each of which includes thin slip zones. Thermal conductivity (K) lies between 1.0 and 3.0 Wm-1K-1 and shows the lowest value at the slip zones. Thermal diffusivity (α) varies between 0.8 to 2.0 ¿ 10-6 m2s-1, and is relatively low at the slip zones. Density (ρ) varies between 2200 to 2800 kgm-3 and shows the lowest values at a particular slip zone (1110 m depth). Specific heat (c) is calculated by using above data resulting in the values from 300 to 1000 Jkg-1K-1, and lowest values for slip zones. Using these data and spectral gamma ray logs, reported positive thermal anomalies at the slip zones are re-examined whether they are regarded as residual heat from friction by faulting.