One of the most important factors which influences on the quality of early childhood education and care(ECEC) is teachers or staff in ECEC centers. They say the quality of ECEC depends on the quality of teachers. The importance of teachers(or staff) in ECEC has been deeply perceived by OECD countries, and OECD started to conduct the TALIS Starting Strong Survey(TALIS 3S) in 2015. The first wave of TALIS 3S began 2015 and will end 2019. Nine countries including Korea is participating in the survey. The present technical report shows the procedure of processing the 2018 main survey of OECD TALIS 3S in Korea. We participated in the NPM meetings which hosted by OECD in both Paris, France and Seoul, Korea to understand the process of the survey and express our progress in Korea. Also, we followed the process leaded by OECD and sent the data collected in Korean ECEC centers. We expect we can analyze the data along with the guideline of OECD and produce the final report including 8 other countries' results in 2019.