Bill Bowman takes over from late North East MSP Alex Johnstone
Mr Johnstone died earlier this month.
Bill Bowman has taken over from North East MSP Alex Johnstone, who died at the age of 55 after a short illness.
Mr Johnstone (pictured) was the longest serving Scottish Conservative member in Parliament.
Mr Bowman, a chartered accountant, stood for the Conservatives in the Dundee City East seat at the Scottish election earlier this year.
He was also in sixth place in the party's North East regional list, meaning he was next in line for a seat at Holyrood.
He took the oath of allegiance in the chamber on Wednesday.
Mr Johnstone's funeral took place last week, while party leaders led tributes to him in a motion of condolence at the Scottish Parliament this week.
Conservative leader Ruth Davidson said the big-hearted'' MSP had beena friend to all''.
First Minister Nicola Sturgeon said he exemplified the integrity, dedication and sense of public service that people expect to see from their elected representatives''.