He recently informed Bulldog officials that increasing work and family commitments led to his decision.
Doswell, 36, led the Bulldogs to their third flag in four years last season after replacing co-coaches Jayden Kotzur and Jamarl O'Sullivan.
"I'm struggling to find the necessary time to devote to coaching with work and family commitments," Doswell said.
Doswell hasn't ruled out extending his career as a player at the kennel.
"I will possibly still play on," he said.
"It will depend mainly on how the body feels in six months time I suppose.
"Trying to maintain a decent level of fitness is going to be hard with no football this year.
"To be honest I've been struggling for motivation fitness-wise and haven't been doing too much with work extremely busy.
"It is my intention to play on if Thurgoona find the right person to coach and bring some players in."
IN OTHER NEWS
The Bulldogs' status as a powerhouse is under threat for the first time in four years.
They lost a host of premiership stars over the summer including Lucas Mellier, Mark Haydon, Aydan Brown, Charlie Williams and Jake Bruce crossing to Rand-Walbundrie-Walla.
Josh Maher and Matt Fowler also retired.
Barton medallist Jayden Kotzur has signed for The Rock-Yerong Creek and has indicated he will also call it quits on his glittering career at seasons end.
While triple premiership ruckman Jamarl O'Sullivan is over 40 and would be seriously contemplating retiring.
Doswell said his replacement would have a huge bearing on the Bulldogs' list.
"If they can find the right coach going forward hopefully they might be able to keep some of those older guys for 12 months," he said.
"But we definitely need an injection of youth and the club is on the front foot in that regard."