The US-owned team, who slumped to 10th and last in the 2023 constructors' standings with only 12 points, said in a statement that the Italian-American had left with immediate effect.
Technical director Simone Resta, who previously worked for engine providers Ferrari, has also left the team.
Steiner became a fan favourite thanks to the Netflix docu-series 'Drive to Survive' in which he features prominently with outbursts of swearing and devastatingly frank and unfiltered assessments.
He also released a best-selling book last year entitled 'Surviving to Drive, a year inside Formula One.'
The departure of a cult hero, unless he pops up again elsewhere in the paddock, will be a blow for many of those recently attracted to the sport.
"Thanks, Guenther. Thanks for taking me on the journey in 2017 and thanks for bringing me on board again in 2022. It has been both fun and tremendously challenging - but never boring," said the team's Danish driver Kevin Magnussen on X.
There was no immediate comment from the ex-boss.
"Always significant when the departing person is not quoted in the press release, tells you there’s friction, suspect we’ll hear more about this," observed Sky television commentator and former driver Martin Brundle.
Steiner led Haas into Formula One on their debut in 2016 and ranked as the third longest-standing principal after Red Bull's Christian Horner and Mercedes' Toto Wolff.
Team owner Gene Haas ultimately called the shots, however, and made clear that his team's current performance was not acceptable.
"Moving forward as an organization it was clear we need to improve our on-track performances," he said in the statement, thanking Steiner for his work and wishing him well for the future.
"In appointing Ayao Komatsu as team principal we fundamentally have engineering at the heart of our management."
Komatsu has also been with the team since the beginning after previous stints at British American Racing (BAR), Renault and Lotus, where he was race engineer for French driver Romain Grosjean.
He will take responsibility for overall strategy and track performance.
The team said a European-based chief operating officer will be appointed to manage all non-competition matters and departments.
"We have had some successes but we need to be consistent in delivering results that help us reach our wider goals as an organization," said Gene Haas.
"We need to be efficient with the resources we have but improving our design and engineering capability is key to our success as a team.
"I'm looking forward to working with Ayao and fundamentally ensuring that we maximize our potential. This truly reflects my desire to compete properly in Formula One."
Haas have yet to win a Grand Prix, or finish on the podium, and their best season was 2018 when they finished fifth overall.
"We obviously haven't been competitive enough recently which has been a source of frustration for us all," said Komatsu.
"We have amazing support from Gene and our various partners and we want to mirror their enthusiasm with an improved on-track product."
The 2024 season starts in Bahrain on March 2nd after testing from February 21st to 23rd.
