Arrested are 21-year-old James Schulz and 19-year-old Amber Caldwell, both of 363 Paradee Drive in Dover.
Detectives were called to the Bay Health Medical Center on August 29th for a report of a possible assault on a 3-month-old.
Investigators say the baby had multiple rib fractures along with several large contusions to the face and head area.
Police say they determined the child had been abused and arrested the parents.
Schulz was being held on $50,000 while Caldwell was being held on $8,000 bond.