The stabbing happened in Camden at a trailer park late Saturday night, police said.
Police said they went to the trailer park after they saw a car they had been searching for that was involved in a missing person case. They said they found the woman, Elizabeth McGuire, inside a trailer.
Investigators said the woman had gone from Hamilton to Camden and was stabbed repeatedly.
At this time, police do not know if the woman was abducted or if she went willingly.
Tim Mikesell with Camden Police said, "That is being investigated. We have made an arrest. We do believe before the victim and arrestee, that there was some type of relationship."
William Whitaker of Hamilton was charged with felonious assault. Mikesell said he met with prosecutors on Monday to discuss the possibility of additional charges.
Residents who live in the trailer park said they were not aware that the person who was reported missing was found stabbed just a few doors down.
Sheriff Mike Simpson said the Whitaker is being held in the Preble County Jail.