This paper describes the thermal properties (effective thermal conductivity and thermal diffusivity) of an organic waste used to model the composting process in relation to volumetric water content at 20 degrees C. The organic waste was a mixture of fresh dairy cattle feces and sawdust with a ratio of one-to-one on a dry weight basis. The thermal probe method was used to determine the effective thermal diffusivity. The effective thermal conductivities were found to increase with volumetric water content, and ranged from 0.0500 to 0.202 W m(-1) K-1 at volumetric water contents of 0% and 44.2%, respectively. The thermal diffusivity was not affected by the volumetric water content, and was found to have a mean value of 1.08 x 10(-7) m(2) s(-1).