Hugh Henry is to succeed Peter Peacock as education minister, the Scottish Executive has confirmed.
The 54-year-old is a former economics and business teacher
Mr Peacock, 54, resigned on health grounds after receiving medical advice for a condition akin to a mild stroke. He remains a Highlands and Islands MSP.
Mr Henry, who has been deputy justice minister for the past four years, is replaced by Johann Lamont.
Labour MSP Des McNulty gets her job as deputy communities minister, a post he was sacked from three years ago.
The new education minister paid tribute to Mr Peacock and said it was an honour to take over from him.
The 54-year-old, a former teacher of economics and business studies, said there was no room for complacency in education.
"I passionately believe that every child in Scotland, whoever they are, wherever they come from, should be given the best opportunities in life - and that starts in the schools," Mr Henry said.
"We can never stand still, and there are still too many children in this country who don't get the best possible start in life."
Mr Henry, Labour MSP for Paisley South, said his top priority would be the completion of the schools building programme.
"I have been absolutely stunned by the quality of the new schools I am seeing in my own area of Renfrewshire," he said.
"I want to make sure that follows through to its completion - I don't want anyone, whoever they are, to do anything that will destabilise that building programme."
In his resignation letter to First Minister Jack McConnell, Mr Peacock said: "As you are aware, I have been experiencing a prolonged period of poor health.
"It has become increasingly apparent that a ministerial lifestyle is not conducive to either promoting or maintaining my health and following further recent difficulties and advice, I have concluded that I must give my health priority attention."
In reply, Mr McConnell praised Mr Peacock's tenure in education, saying the education system was in good shape, morale was high and the number of new teachers entering the profession was "extremely encouraging".
Scottish Conservative leader Annabel Goldie said: "We are sorry to learn that Mr Peacock has had to resign on health grounds and on a personal level we wish him well."
Fiona Hyslop, the Scottish National Party education spokeswoman, thanked the Highlands and Islands list MSP for his contribution to Scottish education.
"Peter Peacock has been the longest serving education minister under devolution and well respected in education circles and in the parliament," she said.
The Scottish Secondary Teachers' Association said his departure was "a significant loss for the education community in Scotland".
The Educational Institute for Scotland said that under Mr Peacock's leadership, Scottish education had moved forward significantly and with a high degree of consensus.