The work aims to introduce the joint coating process and control essentials of Shenzhen-Hongkong submarine pipelines. Epoxy primer, heat shrink sleeves and opening high density polyurethane foam were jointly used in the joint coating of Shenzhen-Hong Kong submarine pipelines. The quality of joint coating was guaranteed by controlling and managing construction materials, equipment, construction personnels and process in an effective manner. The field test conducted after the completion of Shenzhen-Hong Kong submarine pipelines project showed that quality of joint coating met the technical requirements of DNV RP F102 and ISO 21809-3, and the compressive strength and density of polyurethane foam met the design requirements.