Mahaman Moustapha Barke Bako, previously minister of mines, petrol, and energy, will now be minister of petrol.
Professor Amadou Haoua was named the new minister of energy and Col. Ousmane Abarchi was named minister of mines, according to a decree read out on state television, that did not give a reason for the reshuffle.
All three are strategically important sectors for the West African country, where military officers overthrew the democratic government in July.
Niger is one of the world's largest producers of uranium, the most widely used fuel for nuclear energy.
It hopes to boost its oil output to around 110,000 barrels per day, bpd. The nation currently produces around 20,000 bpd with the new Niger-Benin oil pipeline which was launched late last year.