Flexible DC transmission technology can build a flexible and efficient power grid structure，with the advantages of flexible control and self-replacement. It represents the development and research direction of DC transmission field，and has been widely promoted and applied at home and abroad. This paper investigates the development status of equipment reliability standards in the field of flexible DC transmission in China，combs the reliability requirements of flexible DC engineering，and analyzes the current construction of reliability standards in this field. Based on the current status of reliability standards in non-flexible HVDC transmission，the preliminary assumptions for the construction of reliability standards for flexible HVDC transmission systems are proposed，which provides a reference for the construction of reliability standard systems for flexible DC transmission equipment in China.