Mick Potter is to leave Bradford and return Down Under to Australia.
Potter, 48, had been working on a voluntary basis since early July, having been redundant alongside 15 others, and narrowly missed out on guiding the Bulls in to the play-offs, despite a six point deduction.
He had been offered a new deal to stay on at the club, but has opted to move on.
Potter said: “I was always going to return to Australia and I feel that now is the right time for me to go.
“I have enjoyed my time at the Bulls and the supporters and people at the club are second to none.
“I feel too that, despite circumstances beyond our control, the team, through the rugby league we played, showed a lot of character in the midst of terrible adversity.
“Omar Khan and Gerry Sutcliffe have come in and rescued the club, and were keen for me to stay for a longer tenure, and I made it clear to them that my decision has nothing to do with their purchase of the club.
“It has been the things that have happened over the previous five months that have caused my decision.
Potter has recommended that his assistant, Francis Cummins, should take over at Odsal.
In a statement, Khan and Sutcliffe said: “We are sorry Mick has chosen to leave because we wanted him to stay longer with us after the tremendous job he has done in difficult circumstances. He leaves with the best wishes of everyone at the club and we wish him well in the future.
“We hope to be able to announce a new coach early next week.”
He moved on to St Helens, where he reached two Grand Finals, before joining the Bulls ahead of the 2011 season.