A day after Oda announced she was stepping down from her post as international co-operation minister, Harper appointed Julian Fantino to the job.
Fantino, former chief of Toronto police, had been serving as associate minister of national defence.
He's being replaced by Bernard Valcourt, a minister from New Brunswick who will continue his role as minister of state for Atlantic Canada and La Francophonie.
The two have already been sworn into their posts at Rideau Hall.
Harper says the changes ensure continuity and both men bring strong leadership experience to the positions.