Polydimethylsiloxane (PDMS) has widely appeared in different electronic and medical applications. The knowledge of the thermal properties of PDMS and especially its thermal conductivity is required while processing PDMS to design a particular device. In this paper measurement of the thermal conductivity of PDMS using the three omega method is presented at different temperatures. The three omega method has been chosen because of its ease of use and accuracy. It requires the fabrication of metallic lines which act as heaters and thermometers on the surface of the material under test. A different procedure is introduced in this paper through which the metallic lines are embedded in the surface of PDMS. Experimental results are then compared to Cahill's approximate solution and to the results obtained by numerical simulations using a finite element method