In the present work, the effective thermal conductivity of teak wood dust (TWD) filled epoxy composites at different volume fractions (6.5, 11.3, 26.8 and 35.9%) have been determined experimentally by using Lee’s Apparatus. Composites of teak wood dust particles of 150µ, 200µ and 250µ sizes with varying volume fractions (6.5, 11.3, 26.8 and 35.9%) have been developed by hand lay up technique. From the tests it is observed that for each size of TWD, the thermal conductivity values of composites decreases with increase of filler content which indicates that the TWD reinforced epoxy composites have good insulation properties. It has also been found that the composite with 150µ particle size of teak wood dust at same volume fractions exhibited lowest thermal conductivity compared to composites with 200µ and 250µ of teak wood dust. Therefore the composite with particle size 150µ at 35.9% volume fraction teak wood dust may be more suitable for insulation applications. Experimental results (TWD,150µ) are also compared with the theoretical models (such as Rule of Mixture model, Russel model, Maxwell model Baschirow & Selenew model ) and found that the errors associated with all the above four models with respect to experimental ones lie in the range of 20.14 to 84%, 74 to111.84%, 79.13 to 115.79% and 60.13 to 102% respectively.