Haynes Publishing's adjusted pre-tax profits rose by 120% to £1.1m in the six months to the end of November.
Group revenues were up 21% at £16.9m and adjusted EBITDA increased by 29% to £5.3m.
Adjusted basic earnings per share rose by 151% to 5.3p.
The interim dividend is maintained at 3.5p per share.
Chairman Eddie Bell said: 'I am pleased to report that this is the third consecutive set of results where Haynes has demonstrated strong underlying revenue and profit growth since we implemented our global operational, cost and structure review in 2015/16.
'These interim results confirm that Haynes is making clear progress in its turnaround and is on its way to becoming an integrated multi-media content provider.
'Our UK and US operations have returned to profit during the first half of 2017/18, HaynesPro has once again delivered double digit growth in Europe and I am encouraged to see the contribution that our recent acquisitions, OATS and E3 Technical, have made to the group.'
The group also announced that James Bunkum had been promoted to chief operating officer and would step down from his position as chief financial officer.
Haynes said Jeremy Yates-Round, currently managing director consumer publishing, would take on additional responsibility and oversee the commercial activities of the group's consumer digital initiatives as managing director of Haynes Consumer.
And it said Peter van der Galien and Richard Barker would be appointed to the board as executive directors.
It said: 'Peter has been managing director of HaynesPro since 2016 and has played a key role in overseeing the growth in this part of the group. Peter will now take on overall responsibility for the group's professional operations.
'Richard Barker will be promoted to the role of group finance director. Richard is currently the group's UK and European finance director. Richard will also retain his role as group company secretary.'
At 8:20am: (LON:HYNS) Haynes Publishing Group PLC share price was +19p at 221p