Langlands, 53, joins a list of winners that includes some of the biggest names in the Scottish business world, including Aggreko chief executive Rupert Soames and entrepreneur Sir Tom Hunter.
The awards, whose sponsors include The Scotsman, were presented at a lunch at Prestonfield House Hotel. The speakers were Alan Keir, global head of commercial banking at HSBC, and James Naughtie, presenter of BBC Radio Four's Today programme. The event raised 70,000 for a number of Scottish charities.
Michael Welch, the founder and managing director of tyre firm Blackcircles.com, won the young achiever award, beating Dougal Sharp, the founder of brewer Innis & Gunn, and Robert Morrison, who established watch company Tyko Trading.
The award for international trading went to Colin Robertson, the chief executive of bus maker Alexander Dennis.
He was credited with leading the growth of its share of the UK bus market from 30 per cent to 45 per cent and also for opening new markets in North America, Europe and Australasia.
Others nominated in the category included Roy Davis, the chief executive of eye scanner company Optos, and James Milne, the chairman and managing director of Aberdeen engineering firm the Balmoral Group.
Langlands hailed an "extraordinary year" for Wood Group, which included the completion of the $955 million (590m) acquisition of PSN, re-entry into the FTSE's list of top 100 companies and the sale of the group's well support division to GE for $2.8 billion.
He said the award was "unexpected" and that it felt "strange" to be up against Keillor, recently appointed chief executive of the new Wood Group PSN production services business.
"I don't know if I'm glad I won it," said Langlands.
Robertson said he was "proud to run a manufacturing business that led the world in the design of buses". He gave thanks to his management team and his "phenomenal shareholder base", many of whom were in the room including bus tycoon, Brian Souter.
Chris Tiso, the chief executive of outdoor clothing and equipment retailer Tiso and chairman of Sbaat, said of the 29th awards event: "Outstanding achievement for any individual or business under the current circumstances is certainly worthy of recognition making our awards as relevant as ever."