Officials arrested 24-year-old Jarrod Metsker Sunday, according to a news conference from the Wayne County Sheriff's Office.
Reann Murphy was last seen playing outside her mobile park home in Smithville before she was reported missing Saturday evening.
Officials searched the area and later found her body in a dumpster around 1:35 a.m. near the child's home.
Metsker had been a neighbor whom witnesses reported seeing him at the park where Murphy was playing.
Detectives said he would not cooperate with officials. Ohio Bureau of Criminal Investigation and the Wayne County Coroner are investigating her death.
Anyone with information is asked to call the Wayne County Sheriff's Office at 330-287-5750.