Traer is an unincorporated community in Decatur County, Kansas, United States.

A post office was opened in Traer in 1883, and remained in operation until 1971. The town was originally 1 mile west of its present location and was named Connersville, where a post office was established in 1875. When the town was moved in 1883, it was renamed Traer after the city of Traer, Iowa.^{[citation needed]}

The community is served by Oberlin USD 294 public school district.

39°55′42″N 100°39′59″W / 39.92833°N 100.66639°W / 39.92833; -100.66639