Vestas said the move was as a result of its "flexible and scalable manufacturing set up", which is regularly reevaluated.
The reduction is the result of high manufacturing costs, including salary levels, the firm said, adding it needed to strengthen its manufacturing competitiveness.
From the start of January, the facility at Lem will change from a four-shift, 24/7 production schedule to a three-shift, 24/5 schedule.
"Our flexible and scalable production setup is one of the primary elements in our current success, and it is a business strategy we will follow going forward," said Vestas chief operating officer Jean-Marc Lechene.
"It's never easy to say goodbye to good colleagues, but this is unfortunately a necessary step for Vestas to be highly competitive in a global market," Lechene added.
Vestas said it has 2,400 production staff in Denmark but could not comment on numbers at the Lem site.
In its Q3 financial report, released in early November, Vestas said it employed approximately 21,907 people worldwide (as of end September 2016).