Olivesburg is an unincorporated community in northeastern Weller Township, Richland County, Ohio, United States. It is part of the Mansfield Metropolitan Statistical Area. The town is on the bank of the Whetstone Creek, about two miles north of its junction with the Blackfork of the Mohican River. The community is served by the Ashland (44805) post office.

Weller Township is one of the eighteen townships of Richland County, Ohio, United States. It is a part of the Mansfield Metropolitan Statistical Area. The 2020 census found 1,884 people in the township.