"There is no evidence to support any of the claims made in the book, which is a product of pure conjecture for the purposes of profit by the authors and publishers," the company said in a statement.
In the statement, the airline referred to itself as a "national icon" despite its disastrous year.
It said the authors should "be ashamed of themselves" for "seeking to simply cash in on the suffering of the families and undermining the dignity of all of those on board".
New Zealanders Ximin Wang and Paul Weeks were among the 239 people on board MH370.Mr Weeks' wife Danica said although some books written about MH370 were "disgusting", at least the authors had contacted her before they finished writing The Truth Behind the Loss of Flight 370.
She told APNZ it was "irresponsible" to present any speculation as fact, but added: "I'm all for people doing research on this, because we've got nothing. We don't know anything."
Mrs Weeks said she felt sorry for Shah's family. "You're not only coping with losing your husband or your father. You're also coping with people, the world, saying it was him."
Meanwhile, Malaysia Airlines this week extended its chief executive's contract for another 12 months. Ahmad Jauhari Yahya, who is also the company's managing director, is likely to keep the job until September 19, 2015.
"When do you actually get fired for making bad decisions?" Mrs Weeks said. "There've been so many incompetencies."
She said the airline had an attitude problem. "Their handling of this has been just diabolical ... it's like we're all a big inconvenience, to be honest."