Vanjoki’s unit is mainly responsible for developing smartphone technology, an area in which Nokia has been facing stiff competition, especially on the North American market.
On Friday, Nokia announced that the company’s CEO Olli-Pekka Kallasvuo would be replaced by an outsider, Canadian Stephen Elop.
Vanjoki submitted his resignation on Monday. He has a six-month notice period, and will continue to work at Nokia for now.
"I felt the time has come to seek new opportunities in my life," Vanjoki says in a Nokia press release.
"At the same time, I am one hundred per cent committed to doing my best for Nokia until my very last working day,” he adds.