Martin Blunden, who earns around £200,000 a year from his role at the Scottish Fire and Rescue Service (SFRS), has been in post since early 2019.
He replaced Alasdair Hay, who had held the role from its establishment in 2013.
However, following allegations of bullying from staff, it is understood that Mr Blunden was suspended.
Chair of the board, Dr Kirsty Darwent, failed to confirm or deny the allegation against Mr Blunden, but the fire chief’s official Twitter account has also disappeared from the social media website.
Dr Darwent said: “We take any allegation against staff members extremely seriously and have robust procedures in place to ensure complaints are fully investigated.
"Any complaint would be considered confidential while being progressed.”
No details on the nature of the bullying, to whom it was directed, nor information around the investigation of the allegations was shared by the SFRS when asked to comment on Mr Blunden’s suspension.
It is also not known whether community safety minister Ash Regan, who has responsibility for the Scottish Fire and Rescue Service, was aware of the suspension.
When asked, the Scottish Government refused to be drawn and said the issues were “entirely a matter” for the SFRS’s board.
A Scottish Government spokesperson said: “SFRS takes any allegation against staff members extremely seriously and such issues are entirely a matter for the SFRS board.”
Mr Blunden was tweeting from the account @FireScot_Chief as recently as March 20, but the account now states the profile does not exist.
The chief officer role is the most senior professional position at the SFRS and is intended to “provide strategic leadership direction” to the service.
Mr Blunden joined the SFRS following a period of work in South Yorkshire where he was deputy chief officer and had more than 26 years of experience in firefighting across the UK.
He has also served in Buckinghamshire and Hertfordshire Fire and Rescue Service.
Scottish Conservative shadow community safety minister Russell Findlay said: “Complainers and those who are accused of wrongdoing need to have faith in the integrity of the complaints process, which has not always been the case under this SNP Government.
“The public also rightly expect any such allegations to be taken seriously and that investigations should be conducted fairly, timeously and transparently.”
Two Fire Brigades Union representatives did not respond to a request for comment.