Ottoville is a village in Monterey Township, Putnam County, Ohio, United States.

The first plat at Ottoville was made in 1845 for John Otto Bredeich.

[5] The effort at first proved unsuccessful, and the town site was platted again in 1873.

[5] A post office called Otto was established in 1880, and the name was changed to Ottoville in 1881.

[9] As of the census[10] of 2010, there were 976 people, 392 households, and 279 families living in the village.

24.5% of all households were made up of individuals, and 10.2% had someone living alone who was 65 years of age or older.

28.2% of all households were made up of individuals, and 14.4% had someone living alone who was 65 years of age or older.