NBN Co chief executive Bill Morrow will step down from his role by the end of the year, according to the network builder, as the company "prepares to confront the new challenges ahead".
The company said it has begun a global search to find a new leader.
"I believe that as the company prepares to confront the new challenges ahead, this is the right time to hand over the reins for the next phase of this incredible project and for me to plan for the next step in my career."
When Morrow finishes at NBN Co, he will have led the company for four years and nine months.
“The country has been fortunate to have Bill lead this extraordinary project," said NBN Co chairman Dr Ziggy Switkowski. "While we will be sorry to see him leave, Bill has built a resilient, performance-driven organisation which will build on his legacy.”
NBN Co reconfirmed its projections that the NBN rollout will be completed in 2020, though Morrow will not see its completion to the end.
The network builder also said that 80 percent of the population would be able to connect to the network by the end of this year.