Liew Yuen Sien (Chinese: 刘韵仙; pinyin: Liú Yùnxiān; 1901–1975) was a Chinese-born Singaporean educator. She served from 1927 to 1966 as principal of Nanyang Girls' High School (NYGH), a premier all-girls school in Singapore, the longest-serving principal at NYGH. An active proponent of improving the quality of Chinese education and women's education across Southeast Asia and China, she was awarded the Order of the British Empire in 1958 and the Singaporean Presidential Medal in 1967.