Abstract: In order to avoid various operational problems due to the excessive temperature drop of fluid, it is often necessary to thermally insulate subsea oil and gas pipelines. Thermal insulation coating systems for subsea pipelines can be classified as single and double-steel pipe insulation systems. This paper emphatically introduces a number of commonly used foam insulation materials, nonmetal protective coating materials, and several typical single-steel pipe thermal insulation coating systems used in overseas subsea oil and gas pipelines. The feasibility that the single-steel pipe insulation coating system may be used in Chinese offshore oil field is discussed. Economical comparison between single and double-steel pipe insulation coating systems is performed.