Spanish midfielder Christian Delgado and Danish defender Niclas Vemmelund have been signed by new boss Kenny Shields.
These are the sixth and seventh signings for City.
Meanwhile, Stephen Dooley has left Derry and signed for Cork City.
The Portstewart man joined in June 2014 and made 43 appearances for the Candystrips scoring seven goals.
Derry’s first pre-season game will be away to Ballymena on February 5th.