In this paper we report our recent measurements of thermal conductivities of optical coatings by two photothermal methods, namely photothermal reflectance and photothermal deformation technique. We will first give a brief introduction of the principles and the apparatus for the experiments, and then present the measured thermal conductivities of various coatings including oxide layers (SiO2, ZrO2, Ta2O5) on BK7 glass, a MgF2 film on MgF2 substrate and metallic films (Au). The results are compared between the two methods as well as with those previously reported by other techniques and those of the related bulk materials.