The status of development of the open sea test site for wave energy converters in Korea was described in this paper. In order to promote the dissemination of wave energy and to accelerate the technology development of wave energy converters (WECs), Ministry of Oceans and Fisheries in Korea is supporting the project for the development of the open sea test site from 2016. Site selection, design and consent for test site have been completed by the mid of 2018. Constructions of submarine cable & connectors, substations, SCADA system, onshore buildings, performance assessment system, and test site operation system are being under development. They will be finished by the next year (2019). In this paper, the backgrounds, the achievements, and ongoing process for development of the open sea test site for WECs in Korea were reported.