Fires blazed across much of European Russia in August following weeks of drought and record-high temperatures. A thick pall of smoke from the fires covered Moscow for several days.
Although heavy rains have helped quench the fires in much of the country, the southern regions of Volgograd, Saratov and Samara remain hot and dry.
A ministry statement said the new fires were fanned by high winds and some started when the winds caused power lines to cross, shooting off sparks.
The fires were most intense in the Volgograd region, where 380 houses were burned in 20 populated areas. In Saratov, 20 houses burned.
In the Samara region, traffic on a main highway near the automobile manufacturing city of Togliatti was diverted for hours because of fire.
The ministry said its tanker planes and helicopters had made about 60 sorties to drop water on the fires by midday.