Abstract: Marine riser, as the key structure connecting the subsea wellhead with the platform above the sea surface, plays an important role in heat insulation and preservation in the steam injection and circulation process of heavy oil thermal recovery. Silane-nano ceramics is a kind of new heat insulation coating material which is absolutely superior to the other heat insulation materials with low heat conductivity, high heat preservation rate, good water tolerance and strong temperature resistance. Heat insulation tests were firstly carried out on conventional nano ceramics and silane-nano ceramics by means of the infrared-lamp heating method. Then, the actual service conditions of the heat insulation coating were simulated using the self-made riser heating device. Finally, the heat preservation effects of three kinds of riser’s heat insulation coatings were evaluated and the heat insulation and preservation effects of silane-nano ceramics coating with different structures and thicknesses on the risers were analyzed. It is indicated that the heat insulation and preservation rate of silane-nano ceramics in the environment with the inner temperature of 350 ℃ can be over 70% and the heat preservation effect will be better if the heat insulation mode of outer wall coating is adopted. With the increase of coating thickness, the heat insulation effect gets better. And the heat preservation rate can be increased to 80% as the coating is as thick as 500 μm. The development and application of riser’s silane-nano ceramics coating are of great significance to improve the steam flooding effect and reduce the energy consumption.