Orthodox MSP Graham Simpson has blamed for improvement.
Simpson announced his move as he appeared in a press conference in Scotland with Reform Leader Nigel Faraj.
Simpson told reporters that many people would not be surprised to see him, and leaving the conservatives was “a very big wrench”.
She is the second MSP leaving the party’s Holiroad Group in the last week.
Simpson becomes the only current MSP of improvement.
Mitchell Balantine was sitting as a reform member in the Scottish Parliament from January to May 2021, leaving the conservatives last year and seated for a small magic as an independent.
He lost his seat in the May 2021 election.
Simpson has been an MSP for the Central Scotland region since 2016. He is a former journalist with Sun and daily records.
Speaking at a press conference in Broxburn in West Lothian, he said: “It is advisable to say that some of you will not be surprised to see me here, seeing that Scottish Tories are telling my name as a potential guard for months.
“So today, I am giving them what they want, but perhaps not for the reasons they think.
“Except for that party, when I first joined when I was 15 years old, and I have been searching for a lot of souls in the last few weeks.”