Wong Weng Siu (黄婉秀 huáng wǎnxìu; c. 1939 – 27 July 1973), more commonly known as Mimi Wong, was a Singaporean bar hostess who became the first woman to be sentenced to death for murder in Singapore since its independence. Wong was alleged to have murdered Ayako Watanabe, the wife of her Japanese lover Hiroshi Watanabe, on 6 January 1970. Wong was not alone in this crime; her former husband and sweeper Sim Woh Kum had also helped Wong to restrain the victim while Wong repeatedly stabbed the woman to death.