The worst-hit regions were Maradi, Agadez and Niamey
Heavy rains lashing arid Niger since June have killed 35 people and made more than 26,500 homeless, the civil protection agency said on Saturday.
Twenty people died in house collapses, 15 drowned and 24 were injured, a statement said. A total of 26,532 people had to leave their houses, it said.
The worst-hit regions were Maradi in the south east with 10 deaths, Agadez in the north with 10 fatalities and the capital Niamey where eight people died.
A total of 2,500 houses were destroyed and some 50 schools, mosques, shops and grain silos were damaged. Over 700 cattle also perished.
The short rainy seasons wreaks havoc in the dry Sahel country every year. Last year, floods claimed 73 lives and sparked a humanitarian crisis with 2.2 million people needing assistance, according to the United Nations.