Using the CTD data investigated at about 330 stations in the southern Taiwan Strait, the northeastern South China Sea and their adjacent seas in August and September of 1994, this paper anayses the sectional distributions of salinity in 10 selected sections and discusses the possibility of the Kuroshio’s intrusion into the northeastern South China Sea and the southern Taiwan Strait. The results show that: as the main stream of Kuroshio passes by the northern Luzon Strait during the survey period, the “Kuroshio-influenced water” with some hydrological features of the Kuroshio may extend through the Luzon Strait to the sea areas near both the Dongsha Islands and the Taiwan Shoal of the southern Taiwan Strait. Using the CTD data investigated at about 330 stations in the southern Taiwan Strait, the northeastern South China Sea and their adjacent seas in August and September of 1994, this paper anayses the sectional distributions of salinity in 10 selected sections and discusses the possibility of the Kuroshio’s intrusion into the northeastern South China Sea and the southern Taiwan Strait. The results show that: as the main stream of Kuroshio passes by the northern Luzon Strait during the survey period, the “Kuroshio-influenced water” with some hydrological features of the Kuroshio may extend through the Luzon Strait to the sea areas near both the Dongsha Islands and the Taiwan Shoal of the southern Taiwan Strait.