Lily Serna (born 5 July 1986 in Jerusalem) is an Australian mathematician and television presenter, best known for co-presenting the SBS game show Letters and Numbers (2010−2012) and the cooking show Destination Flavour (2012−present).
Born in Jerusalem, Serna attended Cheltenham Girls' High School in Sydney, Australia, and graduated from the University of Technology Sydney in 2009, with a Bachelor of Mathematics and Finance and a Bachelor of International Studies. In August 2010, she began co-presenting Letters and Numbers, as the show's arithmetical guru, while completing honours studying part-time in mathematics with applications in biology, looking at the effects of flooding on the Fitzroy River and Great Barrier Reef. Serna intends to complete a Ph.D. in environmental science.