Abstract: Subsea single bore vertical Christmas tree is a commonly used development equipment for subsea oil and gas fields, which has high operating efficiency and has been widely used abroad. In view of the current situation that horizontal Christmas trees are predominantly used in subsea fields in China and vertical Christmas trees are rarely used, it is necessary to introduce the technical characteristics and application of subsea single bore vertical Christmas tree. In this paper, the technical characteristics, application cases and operation steps of two different structures of subsea single bore vertical Christmas tree are analyzed and studied in detail. Subsea single bore vertical Christmas tree is not only suitable for marginal oil fields within a few kilometers from existing platform facilities, but also suitable for subsea oil and gas fields with a control distance of hundreds of kilometers. It is suggested that subsea single bore vertical Christmas tree should be gradually used in offshore oil and gas fields in China. This paper provides a reference for the optimization of oil tree in subsea oil and gas fields, and has practical engineering reference significance.