Ilse Kristiina ('Tiina') Lillak (born 15 April 1961) is a Finnish former javelin thrower. She is the 1983 world champion and 1984 Olympic silver medalist. She also twice broke the world record, with throws of 72.40 metres in 1982 and 74.76 metres in 1983. The latter distance ranks third on the all-time list with the old javelin model.