Lisa Frances Ondieki (née O'Dea, formerly Martin) (born 12 May 1960 in Gawler, South Australia) is an Australian retired female long-distance runner.
Originally a hurdler, she was initially reluctant to take up marathon. In her first marathon competition in 1983, she took almost five minutes off the Australian record with her time of 2:32:22. She came seventh in the women's marathon event at the 1984 Los Angeles Olympics, finishing the competition in less than two and a half hours for the first time, and competed in that year's Chicago Marathon in a new personal best time of 2:27:40. At the 1985 Pittsburgh Marathon, she competed alongside her husband at the time, Ken Martin; they became the fastest married couple ever in a marathon and won both of their divisions. She won gold medals in marathon at both the 1986 Edinburgh and 1990 Auckland Commonwealth Games (setting a Commonwealth record in the latter games), and won a silver medal at the 1988 Seoul Olympics. After failing to finish the marathon at the 1992 Barcelona Olympics, she won that year's New York City Marathon, setting a course record of 2:24:40 that would last for nine years. Her last Olympic appearance was the 1996 Atlanta Games, where she failed to finish.
She is divorced from Kenyan runner Yobes Ondieki, with whom she has a daughter.