The job cuts in Finland, which account for 16% of its workforce, will happen "sooner rather than later," said chief executive Mikael Hed on its website.
"We have been building our team on assumptions of faster growth than have materialised," he added.
The company has expanded the brand into a TV series, toys, clothing and an animated movie, which is expected to premiere in cinemas in the summer of 2016.
However, the firm has faced scrutiny this year after it reported its net profit had more than halved in 2013 compared to the previous year.
In August, Rovio said Nokia's former chief executive Pekka Rantala would become its next chief executive at the beginning of 2015.