Petrolia is an unincorporated community in Allen County, Kansas, United States.

In 1910, Petrolia had a money order postoffice, an express office, and was a trading point for the neighborhood.

[3] Petrolia is located in Sections 31–32, Township 26 south, Range 18 east.

Less than a mile from the southern border of Allen County, it is situated west of the Neosho River and to the south of Scatter Creek.

The community is served by Chanute USD 413 public school district.