Children aged between one and seven years will be immunised over the week-long nationwide programme, Health Minister Idi Illiassou said.
He called on parents to “massively” support the effort.
The two-billion-CFA-franc (three-million-euro, $3.4-million) cost is being mainly borne by the World Health Organization (WHO), GAVI Alliance, Rotary International and the UN children’s fund, Unicef.
Niger lies in the so-called “meningitis belt” of sub-Saharan Africa, stretching from Senegal in the west to Ethiopia in the east, where outbreaks of the disease are a regular occurrence.
The vaccination programme in Niger is against meningitis A, one of the six groups of meningitis bacteria that can cause epidemics.
The disease is transmitted between people through coughs and sneezes, close contact and cramped living conditions.
The illness causes acute inflammation of the outer layers of the brain and spinal cord, with the most common symptoms being fever, headache and neck stiffness.