Lulu Sun (née Radovčić; born April 14, 2001) is a New Zealand professional tennis player who represents New Zealand in international competitions. She was born in Te Anau, New Zealand, to a Chinese mother and a Croatian father. At the age of five, she moved to Geneva, Switzerland, where she completed her education and developed a deep connection to both New Zealand and Switzerland.
Sun began her professional career in 2022 and has since achieved significant milestones. In August 2024, she reached a career-high singles ranking of world No. 39. One of her most notable performances was at the 2024 Wimbledon Championships, where she advanced to the quarterfinals as an unseeded player. She also reached the final at the Monterrey Open in August 2024, finishing as the runner-up after a close match against Linda Nosková.
In February 2025, Sun achieved a career-high doubles ranking of No. 190. She continues to compete on the WTA Tour, representing New Zealand in various international tournaments.