Fire Chief Dan Alldred says the first floor of the Toll House gave way as the local historical society was wrapping up Sunday evening's tour in Germantown, 13 miles southwest of Dayton.
Alldred says the injuries were not serious and neither person needed to be taken to a hospital.
About 25 people were in the building at the time of the collapse. Some were unable to come down from the second floor of the cabin, built in 1845, and needed to be rescued by firefighters.
Information from: Dayton Daily News, http://www.daytondailynews.com