Lehmann told Fox Sports television in an interview Monday: "That will be it. It will be a case of too much time, too much travel. For me, I've had a great time and really enjoyed the role, and (I'm) loving it still."
The former test batsman last year extended his contract until October 2019, and says he won't seek a new deal. His final year in charge will include Australia's title defense at the one-day international World Cup and then an Ashes series.
Australia regained the Ashes last week by beating England in the third test in Perth, and begins play in the fourth match on Tuesday at the Melbourne Cricket Ground.
Lehmann, 47, became Australia coach in 2013 after the firing of Mickey Arthur. Lehmann's record as coach includes victory in the 2015 World Cup, winning two Ashes series at home and losing two in Britain.