"Earlier today we initiated a number of changes to streamline our operations, focus our resources on our most strategic opportunities, and invest in our future," Chief Executive Officer and founder Mark Pincus said in a note to employees.
"This is the most painful part of an overall cost reduction plan that also includes significant cuts in spending on data hosting, advertising and outside services, primarily contractors," Pincus said in the note.
The Boston Globe reported Wednesday that the office known as Zynga Boston was close to completion of a new game a year after launching " Adventure World," which was later changed to "Indiana Jones Adventure World."
The Boston office, which began with the acquisitions of Conduit Labs and Floodgate Entertainment, eventually grew to about 50 workers.
But Zynga is having trouble keeping up with the ever-changing Internet landscape.
The firm is most famous for the creation of "Farmville," which is a Facebook game. But gaming on Facebook has been in decline and Zynga share values have fallen, the Globe said.
Along with a 5 percent reduction in staff, Zynga is culling 13 older games from its offerings and throttling back on its investment in "The Ville," and Internet game.