| Official Name: | Nenno, Wisconsin |
| Pushpin Map: | Wisconsin#USA |
| Subdivision Type: | Country |
| Subdivision Name: |  United States |
| Subdivision Type1: | State |
| Subdivision Type2: | County |
| Subdivision Name2: | Washington |
| Timezone: | Central (CST) |
| Utc Offset: | -6 |
| Timezone Dst: | CDT |
| Utc Offset Dst: | -5 |
| Elevation Ft: | 1066 |
| Coordinates: | 43.4461°N -88.3914°W |
| Area Code: | 262 |
| Blank Name: | GNIS feature ID |
| Blank Info: | 1570174 |
Nenno is an unincorporated community located in the town of Addison, Washington County, Wisconsin, United States.
Nenno is on the old Yellowstone Trail, one of the first transcontinental highways. The north-south road through Nenno is now Wisconsin Highway 175, but was previously highway 41, and before that highway 15. On the east side of the road across from the old church is a building dating to around 1870 which was a hotel, store, etc. Just to the north of it is an old shed which opens to the south. It was used as a horse stable.[1] The community was named for Prussian emigrant Nicholas "Nick" Nenno. Upon his arrival in 1833, he operated a hotel, general store, and a brewery. The Post Office was opened in June 1857 by its first Postmaster, George Smith.[2]