The Mugla governor's office said in a statement that the bus was travelling today from popular tourist destination of Bodrum to Denizli province when it skidded on a rainy road and tipped over.
The group's Turkish guide was also injured. The governor's office said there were no critical injuries and all were receiving medical treatment in Mugla.
Footage from the private Dogan news agency shows a white overturned bus on a winding road.
Earlier, Turkey's official Anadolu news agency had reported that 10 Russian tourists had been injured in the accident.