Shin Jin-seo (Korean: 신진서; born 17 March 2000) is a South Korean professional Go player. He has won nine major international championships: the LG Cup in 2020, 2022 and 2024; the Chunlan Cup in 2021; the Samsung Cup in 2022; the Ing Cup in 2023; the Quzhou-Lanke Cup in 2024; the Nanyang Cup in 2025, and the Sawpalkosanol World Top Player Championship in 2025. He is the number one ranked Korean player in the Korea Baduk Association's official rankings, a spot which he first reached in November 2018 and has held continuously since January 2020.